How to print raw Zebra EPL (Eltron) commands from ASP.NET directly to the client printer

Overview

The Eltron Programming Language 2 (EPL2) is a robust text (ASCII) based command language used to control most Eltron brand Zebra printer models. EPL2 takes advantage of the intelligent features built into the printer to reduce programming overhead and minimize data transmission time. EPL is one of command printer languages from Zebra Technologies that is supported by their printers as well as by others thermal printer manufactures like SATO, Datamax, Intermec, Godex (by providing EPL firmware emulation software). Zebra printers are widely used in POS (Point Of Sales or Point of Services) scenarios like retail, banking, hospitality, manufacturing, healthcare and more!

The main advantage of using raw Zebra EPL commands for printing instead of using the built-in browser javascript printing (window.print();) is that the printing performance will be way faster and you, as the developer in charge, will have full control on the printer operation; a factor that is key in the aforementioned scenarios. In ASP.NET websites, you'll be able to use raw printing feature thanks to our WebClientPrint for ASP.NET solution that was specially designed for this kind of printing needs.

In this walkthrough, you'll learn how to print raw EPL commands from an ASP.NET website directly to the client printer without displaying a print dialog at all. You'll be able to print Zebra EPL commands to the Default client printer as well as to any other installed printer at the client machine. This solution works with any popular browser like Chrome, Firefox, Opera & Safari on Windows, Linux, Raspberry Pi or Mac systems!

The Zebra EPL commands that we'll use in this article will print out a simple barcode label that will look like this:

A Sample Barcode Label printed from ASP.NET and created by using Zebra EPL commands

How to specify EPL commands in ASP.NET

EPL commands sometimes call for ASCII chars that are non-readable. For instance, be aware that each line of EPL commands must be terminated by a "Line Feed/New Line" char i.e. ASCII Dec 10 which you can escape in your .NET code by using 0x10 or &H10 notation
It's also strongly recommended that you always start a new label by using a "Line Feed/New Line" char as well.

Later on this article, you'll find the Zebra EPL commands that you can use in C# or VB to print the sample receipt shown above.

Requirements

Development/Server-side

  WebClientPrint 6.0 for ASP.NET (or greater)
  ASP.NET 4.6.1+ or ASP.NET Core 2.0+
  Visual Studio 2015+
  jQuery 1.4.1+

Client-side

  WebClientPrint Processor 6.0 for Windows, Linux, Raspberry Pi & Mac

Follow up these steps

• Open Visual Studio and create a new ASP.NET Website naming it PrintEPLSample
• Add a NuGet reference to Neodynamic.SDK.WebClientPrint package to your project
• Now follow up the instructions for each .NET Core, MVC/C#, MVC/VB, SPA/AngularJS+WebAPI, WebForms/CS or WebForms/VB:
  
  
  • ASP.NET Core
  • MVC/C#
  • MVC/VB
  • SPA/AngularJS+WebAPI
  • WebForms/C#
  • WebForms/VB

  Creating/Editing Controllers

  Create a new Controller and name it WebClientPrintAPIController and then copy/paste the following code:

  
  using Neodynamic.SDK.Web;
  using Microsoft.Extensions.Caching.Memory;
  using Microsoft.AspNetCore.Authorization;
  
  [Authorize]
  public class WebClientPrintAPIController : Controller
  {
  	//IMPORTANT NOTE >>>>>>>>>>
  	// We're going to use MemoryCache to store users related staff like
  	// the list of printers and they have the WCPP client utility installed
  	// BUT you can change it based on your dev needs!!!
  	// For instance, you could use a Distributed Cache instead!
  	//>>>>>>>>>>>>>>>>>>>>>>>>>
  	private readonly IMemoryCache _MemoryCache;
  
  	public WebClientPrintAPIController(IMemoryCache memCache)
  	{
  		_MemoryCache = memCache;
  	}
  
  	[AllowAnonymous]
  	public IActionResult ProcessRequest()
  	{
  		//get session ID
  		string sessionID = HttpContext.Request.Query["sid"].ToString();
  
  		//get Query String
  		string queryString = HttpContext.Request.QueryString.Value;
  
  		try
  		{
  			//Determine and get the Type of Request 
  			RequestType prType = WebClientPrint.GetProcessRequestType(queryString);
  
  			if (prType == RequestType.GenPrintScript ||
  				prType == RequestType.GenWcppDetectScript)
  			{
  				//Let WebClientPrint to generate the requested script
  				byte[] script = WebClientPrint.GenerateScript(Url.Action("ProcessRequest", "WebClientPrintAPI", null, HttpContext.Request.Scheme), queryString);
  
  				return File(script, "application/x-javascript", "WebClientPrintScript");
  			}
  			else if (prType == RequestType.ClientSetWcppVersion)
  			{
  				//This request is a ping from the WCPP utility
  				//so store the session ID indicating it has the WCPP installed
  				//also store the WCPP Version if available
  				string wcppVersion = HttpContext.Request.Query["wcppVer"];
  				if (string.IsNullOrEmpty(wcppVersion))
  					wcppVersion = "1.0.0.0";
  
  				_MemoryCache.Set(sessionID + "wcppInstalled", wcppVersion);
  			}
  			else if (prType == RequestType.ClientSetInstalledPrinters)
  			{
  				//WCPP Utility is sending the installed printers at client side
  				//so store this info with the specified session ID
  				string printers = HttpContext.Request.Query["printers"].ToString();
  				if (!string.IsNullOrEmpty(printers) && printers.Length > 0)
  					printers = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printers));
  
  				_MemoryCache.Set(sessionID + "printers", printers);
  
  			}
  			else if (prType == RequestType.ClientSetInstalledPrintersInfo)
  			{
  				//WCPP Utility is sending the client installed printers with detailed info
  				//so store this info with the specified session ID
  				//Printers Info is in JSON format
  				string printersInfo = HttpContext.Request.Form["printersInfoContent"];
  
  				if (string.IsNullOrEmpty(printersInfo) == false)
  					printersInfo = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printersInfo));
  
  				_MemoryCache.Set(sessionID + "printersInfo", printersInfo);
  
  
  			}
  			else if (prType == RequestType.ClientGetWcppVersion)
  			{
  				//return the WCPP version for the specified sid if any
  				bool sidWcppVersion = (_MemoryCache.Get<string>(sessionID + "wcppInstalled") != null);
  
  				return Ok(sidWcppVersion ? _MemoryCache.Get<string>(sessionID + "wcppInstalled") : "");
  
  			}
  			else if (prType == RequestType.ClientGetInstalledPrinters)
  			{
  				//return the installed printers for the specified sid if any
  				bool sidHasPrinters = (_MemoryCache.Get<string>(sessionID + "printers") != null);
  
  				return Ok(sidHasPrinters ? _MemoryCache.Get<string>(sessionID + "printers") : "");
  			}
  			else if (prType == RequestType.ClientGetInstalledPrintersInfo)
  			{
  				//return the installed printers with detailed info for the specified Session ID (sid) if any
  				bool sidHasPrinters = (_MemoryCache.Get<string>(sessionID + "printersInfo") != null);
  
  				return Ok(sidHasPrinters ? _MemoryCache.Get<string>(sessionID + "printersInfo") : "");
  			}
  
  		}
  		catch
  		{
  			return BadRequest();
  		}
  
  		return Ok();
  	}
  }
  

  Edit the HomeController to the following code:

  
  public class HomeController : Controller
  {
      public IActionResult Index()
      {
          ViewData["WCPPDetectionScript"] = Neodynamic.SDK.Web.WebClientPrint.CreateWcppDetectionScript(Url.Action("ProcessRequest", "WebClientPrintAPI", null, Url.ActionContext.HttpContext.Request.Scheme), Url.ActionContext.HttpContext.Session.Id);
  
          return View();
      }
  
      public IActionResult PrintEPL()
      {
          return View();
      }
  
  }
  

  Add a new Controller and name it PrintEPLController and paste the following code:

  
  using Neodynamic.SDK.Web;
  
  public class PrintEPLController : Controller
  {
      private readonly IHostingEnvironment _hostEnvironment;
  
      public PrintEPLController(IHostingEnvironment hostEnvironment)
      {
          _hostEnvironment = hostEnvironment;
      }
  
      public IActionResult Index()
      {
          ViewData["WCPScript"] = Neodynamic.SDK.Web.WebClientPrint.CreateScript(Url.Action("ProcessRequest", "WebClientPrintAPI", null, Url.ActionContext.HttpContext.Request.Scheme), Url.Action("PrintCommands", "PrintEPL", null, Url.ActionContext.HttpContext.Request.Scheme), Url.ActionContext.HttpContext.Session.Id);
  
          return View();
      }
  
  
  	[Microsoft.AspNetCore.Authorization.AllowAnonymous]
      public IActionResult PrintCommands(string useDefaultPrinter, string printerName)
  	{
  		//Create Zebra EPL commands for sample receipt
              
          string lineFeed = "0x0A";
  
          string cmds =  "";
          cmds += lineFeed;
          cmds += "N";
          cmds += lineFeed;
          cmds += "Q609,24";
          cmds += lineFeed;
          cmds += "q784";
          cmds += lineFeed;
          cmds += "A170,5,0,1,5,5,N,\"WORLDWIDE\"";
          cmds += lineFeed;
          cmds += "LO5,230,765,10";
          cmds += lineFeed;
          cmds += "A10,265,0,1,3,3,R,\"MODEL:\"";
          cmds += lineFeed;
          cmds += "A280,265,0,1,3,3,N,\"Bar Code Printer\"";
          cmds += lineFeed;
          cmds += "A10,340,0,1,3,3,R,\" CODE: \"";
          cmds += lineFeed;
          cmds += "B280,340,0,3C,2,6,120,B,\"BCP-1234\"";
          cmds += lineFeed;
          cmds += "LO5,520,765,10";
          cmds += lineFeed;
          cmds += "A100,550,0,1,2,2,N,\"ISO 9000 Made In USA\"";
          cmds += lineFeed;
          cmds += "P1";
          cmds += lineFeed;
  
  
  		//Create a ClientPrintJob and send it back to the client!
  		ClientPrintJob cpj = new ClientPrintJob();
  		//set  EPL commands to print...
  		cpj.PrinterCommands = cmds;
  		cpj.FormatHexValues = true;
  
  		//set client printer...
  		if (useDefaultPrinter == "checked" || printerName == "null")
  			cpj.ClientPrinter = new DefaultPrinter();
  		else
  			cpj.ClientPrinter = new InstalledPrinter(printerName);
  	
  
          return File(cpj.GetContent(), "application/octet-stream");
              
      }
  
  }
  

  Creating/Editing Views

  The default View is for detecting whether the client machine has the WebClientPrint Processor (WCPP) Utility installed. Edit the Views / Shared / _Layout.cshtml file and add the folowing section to the BODY:

  Be sure this View links to jQuery 1.4.1+ file!

  
  <body>
      ...
  	
      @RenderSection("scripts", required: false)
  
  	...
  </body>
  

  Edit the Views / Home / Index.cshtml file and copy/paste the folowing code:

  
  @{
      ViewBag.Title = "Home Page";
  }
  
  
  <div id="msgInProgress">
      <div id="mySpinner" style="width:32px;height:32px"></div>
      <br />
      <h3>Detecting WCPP utility at client side...</h3>
      <h3>Please wait a few seconds...</h3>
      <br />
  </div>
  <div id="msgInstallWCPP" style="display:none;">
      <h3>#1 Install WebClientPrint Processor (WCPP)!</h3>
      <p>
          <strong>WCPP is a native app (without any dependencies!)</strong> that handles all print jobs
          generated by the <strong>WebClientPrint for ASP.NET component</strong> at the server side. The WCPP
          is in charge of the whole printing process and can be
          installed on <strong>Windows, Linux, Mac & Raspberry Pi!</strong>
      </p>
      <p>
          <a href="//www.neodynamic.com/downloads/wcpp/" target="_blank" >Download and Install WCPP from Neodynamic website</a><br />
      </p>
      <h3>#2 After installing WCPP...</h3>
      <p>
          <a asp-controller="PrintEPL" asp-action="Index" >You can go and test the printing page...</a>
      </p>
  
  </div>
  
  @section scripts{
      
  <script type="text/javascript">
  
      var wcppPingTimeout_ms = 60000; //60 sec
      var wcppPingTimeoutStep_ms = 500; //0.5 sec
                   
      function wcppDetectOnSuccess(){
          // WCPP utility is installed at the client side
          // redirect to WebClientPrint sample page
                  
          // get WCPP version
          var wcppVer = arguments[0];
          if(wcppVer.substring(0, 1) == "6")
              window.location.href = '@Url.Action("Index", "PrintEPL")';
          else //force to install WCPP v6.0
              wcppDetectOnFailure();
      }
  
      function wcppDetectOnFailure() {
          // It seems WCPP is not installed at the client side
          // ask the user to install it
          $('#msgInProgress').hide();
          $('#msgInstallWCPP').show();
      }
  
  </script>
  
  
  @* WCPP detection script generated by HomeController *@
  
  @Html.Raw(ViewData["WCPPDetectionScript"])
  
  
      }
  

  Add a new View with the following name and under such folders: Views / PrintEPL / Index.cshtml Then, copy/paste the folowing code:

  
  <h3>Print EPL commands</h3>
  
  <div>
  <label class="checkbox">
  	<input type="checkbox" id="useDefaultPrinter" /> <strong>Print to Default printer</strong> or...
  </label>
  </div>
  
  <div id="loadPrinters">
  	Click to load and select one of the installed printers!
  	<br />
  	 <input type="button" onclick="javascript:jsWebClientPrint.getPrinters();" value="Load installed printers..." />
  	<br /><br />
  </div>
  
  <div id="installedPrinters" style="visibility:hidden">
  	<label for="installedPrinterName">Select an installed Printer:</label>
  	<select name="installedPrinterName" id="installedPrinterName"></select>
  </div>
  
  <script type="text/javascript">
  	var wcppGetPrintersTimeout_ms = 60000; //60 sec
      var wcppGetPrintersTimeoutStep_ms = 500; //0.5 sec
  
  	function wcpGetPrintersOnSuccess() {
  		// Display client installed printers
  		if (arguments[0].length > 0) {
  			var p = arguments[0].split("|");
  			var options = '';
  			for (var i = 0; i < p.length; i++) {
  				options += '<option>' + p[i] + '</option>';
  			}
  			$('#installedPrinters').css('visibility', 'visible');
  			$('#installedPrinterName').html(options);
  			$('#installedPrinterName').focus();
  			$('#loadPrinters').hide();
  		} else {
  			alert("No printers are installed in your system.");
  		}
  	}
  	function wcpGetPrintersOnFailure() {
  		// Do something if printers cannot be got from the client
  		alert("No printers are installed in your system.");
  	}
  </script>
  
  <br />
  
  <input type="button" style="font-size:18px" onclick="javascript:jsWebClientPrint.print('useDefaultPrinter=' + $('#useDefaultPrinter').attr('checked') + '&printerName=' + $('#installedPrinterName').val());" value="Print EPL..." />
  
  
  @section scripts{
      
  @* Register the WebClientPrint script code generated by PrintEPLController. *@
  
  @Html.Raw(ViewData["WCPScript"]);
  
      }
  

  Creating/Editing Controllers

  Create a new Controller and name it WebClientPrintAPIController and then copy/paste the following code:

  
  public class WebClientPrintAPIController : Controller
  {
   
      //*********************************
      // IMPORTANT NOTE 
      // In this sample we store users related stuff (like
      // the list of printers and whether they have the WCPP 
      // client utility installed) in the Application cache
      // object part of ASP.NET BUT you can change it to 
      // another different storage (like a DB or file server)!
      // which will be required in Load Balacing scenarios
      //*********************************
   
      [AllowAnonymous]
      public void ProcessRequest()
      {
          //get session ID
          string sessionID = (HttpContext.Request["sid"] != null ? HttpContext.Request["sid"] : null);
   
          //get Query String
          string queryString = HttpContext.Request.Url.Query;
   
          try
          {
              //Determine and get the Type of Request 
              RequestType prType = WebClientPrint.GetProcessRequestType(queryString);
   
              if (prType == RequestType.GenPrintScript ||
                  prType == RequestType.GenWcppDetectScript)
              {
                  //Let WebClientPrint to generate the requested script
                  byte[] script = WebClientPrint.GenerateScript(Url.Action("ProcessRequest", "WebClientPrintAPI", null, HttpContext.Request.Url.Scheme), queryString);
   
                  HttpContext.Response.ContentType = "text/javascript";
                  HttpContext.Response.BinaryWrite(script);
                  HttpContext.Response.End();
              }
              else if (prType == RequestType.ClientSetWcppVersion)
              {
                  //This request is a ping from the WCPP utility
                  //so store the session ID indicating it has the WCPP installed
                  //also store the WCPP Version if available
                  string wcppVersion = HttpContext.Request["wcppVer"];
                  if (string.IsNullOrEmpty(wcppVersion))
                      wcppVersion = "1.0.0.0";
   
                  HttpContext.Application.Set(sessionID + "wcppInstalled", wcppVersion);
              }
              else if (prType == RequestType.ClientSetInstalledPrinters)
              {
                  //WCPP Utility is sending the installed printers at client side
                  //so store this info with the specified session ID
                  string printers = HttpContext.Request["printers"];
                  if (string.IsNullOrEmpty(printers) == false)
                      printers = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printers));
   
                  HttpContext.Application.Set(sessionID + "printers", printers);
   
              }
              else if (prType == RequestType.ClientSetInstalledPrintersInfo)
              {
                  //WCPP Utility is sending the client installed printers with detailed info
                  //so store this info with the specified session ID
                  //Printers Info is in JSON format
                  string printersInfo = HttpContext.Request.Form["printersInfoContent"];
   
                  if (string.IsNullOrEmpty(printersInfo) == false)
                      printersInfo = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printersInfo));
   
                  HttpContext.Application.Set(sessionID + "printersInfo", printersInfo);
   
   
              }
              else if (prType == RequestType.ClientGetWcppVersion)
              {
                  //return the WCPP version for the specified sid if any
                  bool sidWcppVersion = (HttpContext.Application.Get(sessionID + "wcppInstalled") != null);
   
                  HttpContext.Response.ContentType = "text/plain";
                  HttpContext.Response.Write((sidWcppVersion ? HttpContext.Application.Get(sessionID + "wcppInstalled") : ""));
                  HttpContext.Response.End();
   
              }
              else if (prType == RequestType.ClientGetInstalledPrinters)
              {
                  //return the installed printers for the specified sid if any
                  bool sidHasPrinters = (HttpContext.Application.Get(sessionID + "printers") != null);
   
                  HttpContext.Response.ContentType = "text/plain";
                  HttpContext.Response.Write((sidHasPrinters ? HttpContext.Application.Get(sessionID + "printers") : ""));
                  HttpContext.Response.End();
              }
              else if (prType == RequestType.ClientGetInstalledPrintersInfo)
              {
                  //return the installed printers with detailed info for the specified Session ID (sid) if any
                  bool sidHasPrinters = (HttpContext.Application[sessionID + "printersInfo"] != null);
   
                  HttpContext.Response.ContentType = "text/plain";
                  HttpContext.Response.Write(sidHasPrinters ? HttpContext.Application[sessionID + "printersInfo"] : "");
   
              }
   
          }
          catch (Exception ex)
          {
              HttpContext.Response.StatusCode = 500;
              HttpContext.Response.ContentType = "text/plain";
              HttpContext.Response.Write(ex.Message + " - StackTrace: " + ex.StackTrace);
              HttpContext.Response.End();
          }
   
               
      }
  }
  

  Edit the HomeController to the following code:

  
  public class HomeController : Controller
  {
      public ActionResult Index()
      {
  
          ViewBag.WCPPDetectionScript = Neodynamic.SDK.Web.WebClientPrint.CreateWcppDetectionScript(Url.Action("ProcessRequest", "WebClientPrintAPI", null, HttpContext.Request.Url.Scheme), HttpContext.Session.SessionID);
  
          return View();
      }
  
      public ActionResult PrintEPL()
      {
          return View();
      }
  
  }
  

  Add a new Controller and name it PrintEPLController and paste the following code:

  
  using Neodynamic.SDK.Web;
  
  public class PrintEPLController : Controller
  {
  	public ActionResult Index()
  	{
  		ViewBag.WCPScript = WebClientPrint.CreateScript(Url.Action("ProcessRequest", "WebClientPrintAPI", null, HttpContext.Request.Url.Scheme), Url.Action("PrintCommands", "PrintEPL", null, HttpContext.Request.Url.Scheme), HttpContext.Session.SessionID);
  
  		return View();
  	}
  
  	[AllowAnonymous]
  	public void PrintCommands(string useDefaultPrinter, string printerName)
  	{
  		//Create Zebra EPL commands for sample receipt
              
          string lineFeed = "0x0A";
  
          string cmds =  "";
          cmds += lineFeed;
          cmds += "N";
          cmds += lineFeed;
          cmds += "Q609,24";
          cmds += lineFeed;
          cmds += "q784";
          cmds += lineFeed;
          cmds += "A170,5,0,1,5,5,N,\"WORLDWIDE\"";
          cmds += lineFeed;
          cmds += "LO5,230,765,10";
          cmds += lineFeed;
          cmds += "A10,265,0,1,3,3,R,\"MODEL:\"";
          cmds += lineFeed;
          cmds += "A280,265,0,1,3,3,N,\"Bar Code Printer\"";
          cmds += lineFeed;
          cmds += "A10,340,0,1,3,3,R,\" CODE: \"";
          cmds += lineFeed;
          cmds += "B280,340,0,3C,2,6,120,B,\"BCP-1234\"";
          cmds += lineFeed;
          cmds += "LO5,520,765,10";
          cmds += lineFeed;
          cmds += "A100,550,0,1,2,2,N,\"ISO 9000 Made In USA\"";
          cmds += lineFeed;
          cmds += "P1";
          cmds += lineFeed;
  
  		//Create a ClientPrintJob and send it back to the client!
  		ClientPrintJob cpj = new ClientPrintJob();
  		//set Zebra EPL commands to print...
  		cpj.PrinterCommands = cmds;
  		cpj.FormatHexValues = true;
  
  		//set client printer...
  		if (useDefaultPrinter == "checked" || printerName == "null")
  			cpj.ClientPrinter = new DefaultPrinter();
  		else
  			cpj.ClientPrinter = new InstalledPrinter(printerName);
  		
  		//send it...
  		System.Web.HttpContext.Current.Response.ContentType = "application/octet-stream";
  		System.Web.HttpContext.Current.Response.BinaryWrite(cpj.GetContent());
  		System.Web.HttpContext.Current.Response.End();
  		
  	}
  
  }
  

  Creating/Editing Views

  The default View is for detecting whether the client machine has the WebClientPrint Processor (WCPP) Utility installed. Edit the Views / Shared / _Layout.cshtml file and add the folowing section to the BODY:

  Be sure this View links to jQuery 1.4.1+ file!

  
  <body>
      ...
  	
      @RenderSection("scripts", required: false)
  
  	...
  </body>
  

  Edit the Views / Home / Index.cshtml file and copy/paste the folowing code:

  
  @{
      ViewBag.Title = "Home Page";
  }
  
  
  <div id="msgInProgress">
      <div id="mySpinner" style="width:32px;height:32px"></div>
      <br />
      <h3>Detecting WCPP utility at client side...</h3>
      <h3>Please wait a few seconds...</h3>
      <br />
  </div>
  <div id="msgInstallWCPP" style="display:none;">
      <h3>#1 Install WebClientPrint Processor (WCPP)!</h3>
      <p>
          <strong>WCPP is a native app (without any dependencies!)</strong> that handles all print jobs
          generated by the <strong>WebClientPrint for ASP.NET component</strong> at the server side. The WCPP
          is in charge of the whole printing process and can be
          installed on <strong>Windows, Linux, Mac & Raspberry Pi!</strong>
      </p>
      <p>
          <a href="//www.neodynamic.com/downloads/wcpp/" target="_blank" >Download and Install WCPP from Neodynamic website</a><br />
      </p>
      <h3>#2 After installing WCPP...</h3>
      <p>
          <a href="@Url.Action("Index", "PrintEPL")" >You can go and test the printing page...</a>
      </p>
  
  </div>
  
  @section scripts{
      
  <script type="text/javascript">
  
      var wcppPingTimeout_ms = 60000; //60 sec
      var wcppPingTimeoutStep_ms = 500; //0.5 sec
                       
      function wcppDetectOnSuccess(){
          // WCPP utility is installed at the client side
          // redirect to WebClientPrint sample page
                  
          // get WCPP version
          var wcppVer = arguments[0];
          if(wcppVer.substring(0, 1) == "6")
              window.location.href = '@Url.Action("Index", "PrintEPL")';
          else //force to install WCPP v6.0
              wcppDetectOnFailure();
      }
  
      function wcppDetectOnFailure() {
          // It seems WCPP is not installed at the client side
          // ask the user to install it
          $('#msgInProgress').hide();
          $('#msgInstallWCPP').show();
      }
  
  </script>
  
  
  @* WCPP detection script generated by HomeController *@
  
  @Html.Raw(ViewBag.WCPPDetectionScript)
  
  
      }
  

  Add a new View with the following name and under such folders: Views / PrintEPL / Index.cshtml Then, copy/paste the folowing code:

  
  <h3>Print EPL commands</h3>
  
  <div>
  <label class="checkbox">
  	<input type="checkbox" id="useDefaultPrinter" /> <strong>Print to Default printer</strong> or...
  </label>
  </div>
  
  <div id="loadPrinters">
  	Click to load and select one of the installed printers!
  	<br />
  	 <input type="button" onclick="javascript:jsWebClientPrint.getPrinters();" value="Load installed printers..." />
  	<br /><br />
  </div>
  
  <div id="installedPrinters" style="visibility:hidden">
  	<label for="installedPrinterName">Select an installed Printer:</label>
  	<select name="installedPrinterName" id="installedPrinterName"></select>
  </div>
  
  <script type="text/javascript">
  	var wcppGetPrintersTimeout_ms = 60000; //60 sec
      var wcppGetPrintersTimeoutStep_ms = 500; //0.5 sec
  	
      function wcpGetPrintersOnSuccess() {
  		// Display client installed printers
  		if (arguments[0].length > 0) {
  			var p = arguments[0].split("|");
  			var options = '';
  			for (var i = 0; i < p.length; i++) {
  				options += '<option>' + p[i] + '</option>';
  			}
  			$('#installedPrinters').css('visibility', 'visible');
  			$('#installedPrinterName').html(options);
  			$('#installedPrinterName').focus();
  			$('#loadPrinters').hide();
  		} else {
  			alert("No printers are installed in your system.");
  		}
  	}
  	function wcpGetPrintersOnFailure() {
  		// Do something if printers cannot be got from the client
  		alert("No printers are installed in your system.");
  	}
  </script>
  
  <br />
  
  <input type="button" style="font-size:18px" onclick="javascript:jsWebClientPrint.print('useDefaultPrinter=' + $('#useDefaultPrinter').attr('checked') + '&printerName=' + $('#installedPrinterName').val());" value="Print EPL..." />
  
  
  @section scripts{
      
  @* Register the WebClientPrint script code generated by PrintEPLController. *@
  
  @Html.Raw(ViewBag.WCPScript);
  
      }
  

  Creating/Editing Controllers

  Create a new Controller and name it WebClientPrintAPIController and then copy/paste the following code:

  
  Imports Neodynamic.SDK.Web
   
  Namespace Controllers
      Public Class WebClientPrintAPIController
          Inherits Controller
   
          ' GET: WebClientPrintAPI
          Function Index() As ActionResult
              Return View()
          End Function
   
          '*********************************
          ' IMPORTANT NOTE 
          ' In this sample we store users related stuff (like
          ' the list of printers and whether they have the WCPP 
          ' client utility installed) in the Application cache
          ' object part of ASP.NET BUT you can change it to 
          ' another different storage (like a DB or file server)!
          ' which will be required in Load Balacing scenarios
          '*********************************
   
          <AllowAnonymous>
          Public Sub ProcessRequest()
              'get session ID
              Dim sessionID As String = (If(HttpContext.Request("sid") IsNot Nothing, HttpContext.Request("sid"), Nothing))
   
              'get Query String
              Dim queryString As String = HttpContext.Request.Url.Query
   
              Try
                  'Determine and get the Type of Request 
                  Dim prType As RequestType = WebClientPrint.GetProcessRequestType(queryString)
   
                  If prType = RequestType.GenPrintScript OrElse prType = RequestType.GenWcppDetectScript Then
                      'Let WebClientPrint to generate the requested script
                      Dim script As Byte() = WebClientPrint.GenerateScript(Url.Action("ProcessRequest", "WebClientPrintAPI", Nothing, HttpContext.Request.Url.Scheme), queryString)
   
                      HttpContext.Response.ContentType = "text/javascript"
                      HttpContext.Response.BinaryWrite(script)
                      HttpContext.Response.End()
   
                  ElseIf prType = RequestType.ClientSetWcppVersion Then
                      'This request is a ping from the WCPP utility
                      'so store the session ID indicating it has the WCPP installed
                      'also store the WCPP Version if available
                      Dim wcppVersion As String = HttpContext.Request("wcppVer")
                      If String.IsNullOrEmpty(wcppVersion) Then
                          wcppVersion = "1.0.0.0"
                      End If
   
                      HttpContext.Application.Set(sessionID & "wcppInstalled", wcppVersion)
   
                  ElseIf prType = RequestType.ClientSetInstalledPrinters Then
                      'WCPP Utility is sending the installed printers at client side
                      'so store this info with the specified session ID
                      Dim printers As String = HttpContext.Request("printers")
                      If String.IsNullOrEmpty(printers) = False Then
                          printers = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printers))
                      End If
   
   
                      HttpContext.Application.Set(sessionID & "printers", printers)
   
                  ElseIf prType = RequestType.ClientSetInstalledPrintersInfo Then
                      'WCPP Utility is sending the installed printers at client side
                      'so store this info with the specified session ID
                      'Printers Info is in JSON format
                      Dim printersInfo As String = HttpContext.Request.Form("printersInfoContent")
                      If Not String.IsNullOrEmpty(printersInfo) Then
                          printersInfo = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printersInfo))
                      End If
   
                      HttpContext.Application.Set(sessionID & "printersInfo", printersInfo)
   
   
                  ElseIf prType = RequestType.ClientGetWcppVersion Then
                      'return the WCPP version for the specified sid if any
                      Dim sidWcppVersion As Boolean = (HttpContext.Application(sessionID & "wcppInstalled") IsNot Nothing)
   
                      HttpContext.Response.ContentType = "text/plain"
                      If (sidWcppVersion) Then
                          HttpContext.Response.Write(HttpContext.Application(sessionID & "wcppInstalled").ToString())
                      End If
                      HttpContext.Response.End()
   
                  ElseIf prType = RequestType.ClientGetInstalledPrinters Then
                      'return the installed printers for the specified sid if any
                      Dim sidHasPrinters As Boolean = (HttpContext.Application(sessionID & "printers") IsNot Nothing)
   
                      HttpContext.Response.ContentType = "text/plain"
                      If (sidHasPrinters) Then
                          HttpContext.Response.Write(HttpContext.Application(sessionID & "printers").ToString())
                      End If
                      HttpContext.Response.End()
   
                  ElseIf prType = RequestType.ClientGetInstalledPrintersInfo Then
                      'return the installed printers with detailed info for the specified Session ID (sid) if any
                      Dim sidHasPrinters As Boolean = (HttpContext.Application(sessionID & "printersInfo") IsNot Nothing)
   
                      HttpContext.Response.ContentType = "text/plain"
   
                      If (sidHasPrinters) Then
                          HttpContext.Response.Write(HttpContext.Application(sessionID & "printersInfo").ToString())
                      End If
                      HttpContext.Response.End()
                  End If
              Catch ex As Exception
                  HttpContext.Response.StatusCode = 500
                  HttpContext.Response.ContentType = "text/plain"
                  HttpContext.Response.Write(ex.Message + " - StackTrace: " + ex.StackTrace)
                  HttpContext.Response.End()
              End Try
   
   
          End Sub
   
      End Class
  End Namespace
  

  Edit the HomeController to the following code:

  
  Public Class HomeController
      Inherits System.Web.Mvc.Controller
  
      Function Index() As ActionResult
          ViewData("WCPPDetectionScript") = Neodynamic.SDK.Web.WebClientPrint.CreateWcppDetectionScript(Url.Action("ProcessRequest", "WebClientPrintAPI", Nothing, HttpContext.Request.Url.Scheme), HttpContext.Session.SessionID)
  
          Return View()
      End Function
  
      Function PrintEPL() As ActionResult
  
          Return View()
      End Function
  
  End Class
  

  Add a new Controller and name it PrintEPLController and paste the following code:

  
  Imports Neodynamic.SDK.Web
  
  Namespace Controllers
      Public Class PrintEPLController
          Inherits Controller
  
          Function Index() As ActionResult
  
              ViewData("WCPScript") = Neodynamic.SDK.Web.WebClientPrint.CreateScript(Url.Action("ProcessRequest", "WebClientPrintAPI", Nothing, HttpContext.Request.Url.Scheme), Url.Action("PrintCommands", "PrintEPL", Nothing, HttpContext.Request.Url.Scheme), HttpContext.Session.SessionID)
  
              Return View()
          End Function
  
          <AllowAnonymous> Public Sub PrintCommands(useDefaultPrinter As String, printerName As String)
  
              'Create Zebra EPL commands for sample label
  
              Dim lineFeed As String = "0x0A"
  
              Dim cmds As String
              cmds += lineFeed
              cmds += "N"
              cmds += lineFeed
              cmds += "Q609,24"
              cmds += lineFeed
              cmds += "q784"
              cmds += lineFeed
              cmds += "A170,5,0,1,5,5,N,""WORLDWIDE"""
              cmds += lineFeed
              cmds += "LO5,230,765,10"
              cmds += lineFeed
              cmds += "A10,265,0,1,3,3,R,""MODEL:"""
              cmds += lineFeed
              cmds += "A280,265,0,1,3,3,N,""Bar Code Printer"""
              cmds += lineFeed
              cmds += "A10,340,0,1,3,3,R,"" CODE: """
              cmds += lineFeed
              cmds += "B280,340,0,3C,2,6,120,B,""BCP-1234"""
              cmds += lineFeed
              cmds += "LO5,520,765,10"
              cmds += lineFeed
              cmds += "A100,550,0,1,2,2,N,""ISO 9000 Made In USA"""
              cmds += lineFeed
              cmds += "P1"
              cmds += lineFeed
  
  		    'Create a ClientPrintJob and send it back to the client!
  		    Dim cpj As New ClientPrintJob()
  		    'set Zebra EPL commands to print...
  		    cpj.PrinterCommands = cmds
  		    cpj.FormatHexValues = True    
  
              If (useDefaultPrinter = "checked" OrElse printerName = "null") Then
                  cpj.ClientPrinter = New DefaultPrinter()
              Else
                  cpj.ClientPrinter = New InstalledPrinter(System.Web.HttpUtility.UrlDecode(printerName))
              End If
  
              System.Web.HttpContext.Current.Response.ContentType = "application/octet-stream"
              System.Web.HttpContext.Current.Response.BinaryWrite(cpj.GetContent())
              System.Web.HttpContext.Current.Response.End()
  
          End Sub
      End Class
  End Namespace
  

  Creating/Editing Views

  The default View is for detecting whether the client machine has the WebClientPrint Processor (WCPP) Utility installed. Edit the Views / Shared / _Layout.vbhtml file and add the folowing section to the BODY:

  Be sure this View links to jQuery 1.4.1+ file!

  
  <body>
      ...
  	
      @RenderSection("scripts", required: False)
  
  	...
  </body>
  

  Edit the Views / Home / Index.vbhtml file and copy/paste the folowing code:

  
  @Code
      ViewData("Title") = "Home Page"
  End Code
  
  
  <div id="msgInProgress">
      <div id="mySpinner" style="width:32px;height:32px"></div>
      <br />
      <h3>Detecting WCPP utility at client side...</h3>
      <h3>Please wait a few seconds...</h3>
      <br />
  </div>
  <div id="msgInstallWCPP" style="display:none;">
      <h3>#1 Install WebClientPrint Processor (WCPP)!</h3>
      <p>
          <strong>WCPP is a native app (without any dependencies!)</strong> that handles all print jobs
          generated by the <strong>WebClientPrint for ASP.NET component</strong> at the server side. The WCPP
          is in charge of the whole printing process and can be
          installed on <strong>Windows, Linux, Mac & Raspberry Pi!</strong>
      </p>
      <p>
          <a href="//www.neodynamic.com/downloads/wcpp/" target="_blank" >Download and Install WCPP from Neodynamic website</a><br />
      </p>
      <h3>#2 After installing WCPP...</h3>
      <p>
          <a href="@Url.Action("Index", "PrintEPL")" >You can go and test the printing page...</a>
      </p>
  
  </div>
  
  @section scripts
      
  <script type="text/javascript">
  
      var wcppPingTimeout_ms = 60000; //60 sec
      var wcppPingTimeoutStep_ms = 500; //0.5 sec
                   
      function wcppDetectOnSuccess(){
          // WCPP utility is installed at the client side
          // redirect to WebClientPrint sample page
                  
          // get WCPP version
          var wcppVer = arguments[0];
          if(wcppVer.substring(0, 1) == "6")
              window.location.href = '@Url.Action("Index", "PrintEPL")';
          else //force to install WCPP v6.0
              wcppDetectOnFailure();
      }
  
      function wcppDetectOnFailure() {
          // It seems WCPP is not installed at the client side
          // ask the user to install it
          $('#msgInProgress').hide();
          $('#msgInstallWCPP').show();
      }
  
  </script>
  
  
  @* WCPP detection script generated by HomeController *@
  
  @Html.Raw(ViewData("WCPPDetectionScript"))
  
  
      }
  
  End Section
  

  Add a new View with the following name and under such folders: Views / PrintEPL / Index.vbhtml Then, copy/paste the folowing code:

  
  <h3>Print EPL commands</h3>
  
  <div>
  <label class="checkbox">
  	<input type="checkbox" id="useDefaultPrinter" /> <strong>Print to Default printer</strong> or...
  </label>
  </div>
  
  <div id="loadPrinters">
  	Click to load and select one of the installed printers!
  	<br />
  	 <input type="button" onclick="javascript:jsWebClientPrint.getPrinters();" value="Load installed printers..." />
  	<br /><br />
  </div>
  
  <div id="installedPrinters" style="visibility:hidden">
  	<label for="installedPrinterName">Select an installed Printer:</label>
  	<select name="installedPrinterName" id="installedPrinterName"></select>
  </div>
  
  <script type="text/javascript">
  	var wcppGetPrintersTimeout_ms = 60000; //60 sec
      var wcppGetPrintersTimeoutStep_ms = 500; //0.5 sec
  
  	function wcpGetPrintersOnSuccess() {
  		// Display client installed printers
  		if (arguments[0].length > 0) {
  			var p = arguments[0].split("|");
  			var options = '';
  			for (var i = 0; i < p.length; i++) {
  				options += '<option>' + p[i] + '</option>';
  			}
  			$('#installedPrinters').css('visibility', 'visible');
  			$('#installedPrinterName').html(options);
  			$('#installedPrinterName').focus();
  			$('#loadPrinters').hide();
  		} else {
  			alert("No printers are installed in your system.");
  		}
  	}
  	function wcpGetPrintersOnFailure() {
  		// Do something if printers cannot be got from the client
  		alert("No printers are installed in your system.");
  	}
  </script>
  
  <br />
  
  <input type="button" style="font-size:18px" onclick="javascript:jsWebClientPrint.print('useDefaultPrinter=' + $('#useDefaultPrinter').attr('checked') + '&printerName=' + $('#installedPrinterName').val());" value="Print EPL..." />
  
  
  @section scripts
      
      @* Register the WebClientPrint script code generated by PrintEPLController. *@
  
      @Html.Raw(ViewData("WCPScript"))
  
  @end section
  

  Creating/Editing Controllers

  Create a new Controller and name it WebClientPrintAPIController and then copy/paste the following code:

  
  public class WebClientPrintAPIController : Controller
  {
   
      //*********************************
      // IMPORTANT NOTE 
      // In this sample we store users related stuff (like
      // the list of printers and whether they have the WCPP 
      // client utility installed) in the Application cache
      // object part of ASP.NET BUT you can change it to 
      // another different storage (like a DB or file server)!
      // which will be required in Load Balacing scenarios
      //*********************************
      [AllowAnonymous]
      public void ProcessRequest()
      {
          //get session ID
          string sessionID = (HttpContext.Request["sid"] != null ? HttpContext.Request["sid"] : null);
   
          //get Query String
          string queryString = HttpContext.Request.Url.Query;
   
          try
          {
              //Determine and get the Type of Request 
              RequestType prType = WebClientPrint.GetProcessRequestType(queryString);
   
              if (prType == RequestType.GenPrintScript ||
                  prType == RequestType.GenWcppDetectScript)
              {
                  //Let WebClientPrint to generate the requested script
                  byte[] script = WebClientPrint.GenerateScript(Url.Action("ProcessRequest", "WebClientPrintAPI", null, HttpContext.Request.Url.Scheme), queryString);
   
                  HttpContext.Response.ContentType = "text/javascript";
                  HttpContext.Response.BinaryWrite(script);
                  HttpContext.Response.End();
              }
              else if (prType == RequestType.ClientSetWcppVersion)
              {
                  //This request is a ping from the WCPP utility
                  //so store the session ID indicating it has the WCPP installed
                  //also store the WCPP Version if available
                  string wcppVersion = HttpContext.Request["wcppVer"];
                  if (string.IsNullOrEmpty(wcppVersion))
                      wcppVersion = "1.0.0.0";
   
                  HttpContext.Application.Set(sessionID + "wcppInstalled", wcppVersion);
              }
              else if (prType == RequestType.ClientSetInstalledPrinters)
              {
                  //WCPP Utility is sending the installed printers at client side
                  //so store this info with the specified session ID
                  string printers = HttpContext.Request["printers"];
                  if (string.IsNullOrEmpty(printers) == false)
                      printers = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printers));
   
                  HttpContext.Application.Set(sessionID + "printers", printers);
   
              }
              else if (prType == RequestType.ClientSetInstalledPrintersInfo)
              {
                  //WCPP Utility is sending the client installed printers with detailed info
                  //so store this info with the specified session ID
                  //Printers Info is in JSON format
                  string printersInfo = HttpContext.Request.Form["printersInfoContent"];
   
                  if (string.IsNullOrEmpty(printersInfo) == false)
                      printersInfo = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printersInfo));
   
                  HttpContext.Application.Set(sessionID + "printersInfo", printersInfo);
   
   
              }
              else if (prType == RequestType.ClientGetWcppVersion)
              {
                  //return the WCPP version for the specified sid if any
                  bool sidWcppVersion = (HttpContext.Application.Get(sessionID + "wcppInstalled") != null);
   
                  HttpContext.Response.ContentType = "text/plain";
                  HttpContext.Response.Write((sidWcppVersion ? HttpContext.Application.Get(sessionID + "wcppInstalled") : ""));
                  HttpContext.Response.End();
   
              }
              else if (prType == RequestType.ClientGetInstalledPrinters)
              {
                  //return the installed printers for the specified sid if any
                  bool sidHasPrinters = (HttpContext.Application.Get(sessionID + "printers") != null);
   
                  HttpContext.Response.ContentType = "text/plain";
                  HttpContext.Response.Write((sidHasPrinters ? HttpContext.Application.Get(sessionID + "printers") : ""));
                  HttpContext.Response.End();
              }
              else if (prType == RequestType.ClientGetInstalledPrintersInfo)
              {
                  //return the installed printers with detailed info for the specified Session ID (sid) if any
                  bool sidHasPrinters = (HttpContext.Application[sessionID + "printersInfo"] != null);
   
                  HttpContext.Response.ContentType = "text/plain";
                  HttpContext.Response.Write(sidHasPrinters ? HttpContext.Application[sessionID + "printersInfo"] : "");
   
              }
   
          }
          catch (Exception ex)
          {
              HttpContext.Response.StatusCode = 500;
              HttpContext.Response.ContentType = "text/plain";
              HttpContext.Response.Write(ex.Message + " - StackTrace: " + ex.StackTrace);
              HttpContext.Response.End();
          }
   
               
      }
       
  }
  

  Add a new Controller and name it PrintEPLController and paste the following code:

  
  using Neodynamic.SDK.Web;
  
  public class PrintEPLController : Controller
  {
  	public ActionResult Index()
  	{
  		return View();
  	}
  
  	[AllowAnonymous]
  	public void PrintCommands(string useDefaultPrinter, string printerName)
  	{
  		//Create Zebra EPL commands for sample receipt
              
          string lineFeed = "0x0A";
  
          string cmds =  "";
          cmds += lineFeed;
          cmds += "N";
          cmds += lineFeed;
          cmds += "Q609,24";
          cmds += lineFeed;
          cmds += "q784";
          cmds += lineFeed;
          cmds += "A170,5,0,1,5,5,N,\"WORLDWIDE\"";
          cmds += lineFeed;
          cmds += "LO5,230,765,10";
          cmds += lineFeed;
          cmds += "A10,265,0,1,3,3,R,\"MODEL:\"";
          cmds += lineFeed;
          cmds += "A280,265,0,1,3,3,N,\"Bar Code Printer\"";
          cmds += lineFeed;
          cmds += "A10,340,0,1,3,3,R,\" CODE: \"";
          cmds += lineFeed;
          cmds += "B280,340,0,3C,2,6,120,B,\"BCP-1234\"";
          cmds += lineFeed;
          cmds += "LO5,520,765,10";
          cmds += lineFeed;
          cmds += "A100,550,0,1,2,2,N,\"ISO 9000 Made In USA\"";
          cmds += lineFeed;
          cmds += "P1";
          cmds += lineFeed;
  
  
  		//Create a ClientPrintJob and send it back to the client!
  		ClientPrintJob cpj = new ClientPrintJob();
  		//set  EPL commands to print...
  		cpj.PrinterCommands = cmds;
  		cpj.FormatHexValues = true;
  
  		//set client printer...
  		if (useDefaultPrinter == "checked" || printerName == "null")
  			cpj.ClientPrinter = new DefaultPrinter();
  		else
  			cpj.ClientPrinter = new InstalledPrinter(printerName);
  		
  		//send it...
  		System.Web.HttpContext.Current.Response.ContentType = "application/octet-stream";
  		System.Web.HttpContext.Current.Response.BinaryWrite(cpj.GetContent());
  		System.Web.HttpContext.Current.Response.End();
  		
  	}
  
  }
  

  Creating SPA by using AngularJS

  Create a new index.html file that will act as our view for detecting whether the client machine has the WebClientPrint Processor (WCPP) Utility installed as well as for listing client printers and to finally perform client side printing. This SPA features two parts or sections, one for "Detecting WCPP" and the other one for "Client side printing". The ClientPrintJob is generated by the controller created above from the Web API server side code. Copy/Paste the following markup:

  Be sure this html file links to jQuery 1.4.1+ and to AngularJS 1.6.4+ files!

  
  <!DOCTYPE html>
  <html>
  <head>
      <title></title>
  	<meta charset="utf-8" />
      <script src="https://code.jquery.com/jquery-1.12.4.min.js"></script>
      <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.4/angular.min.js"></script>
  </head>
  <body>
  
      <div ng-app="myApp" ng-controller="myCtrl">
  
          <div id="wcppDetection">
              <div id="msgInProgress">
                  <div id="mySpinner" style="width:32px;height:32px"></div>
                  <br />
                  <h3>Detecting WCPP utility at client side...</h3>
                  <h3>Please wait a few seconds...</h3>
                  <br />
              </div>
              <div id="msgInstallWCPP" style="display:none;">
                  <h3>#1 Install WebClientPrint Processor (WCPP)!</h3>
                  <p>
                      <strong>WCPP is a native app (without any dependencies!)</strong> that handles all print jobs
                      generated by the <strong>WebClientPrint for ASP.NET component</strong> at the server side. The WCPP
                      is in charge of the whole printing process and can be
                      installed on <strong>Windows, Linux, Mac & Raspberry Pi!</strong>
                  </p>
                  <p>
                      <a href="//www.neodynamic.com/downloads/wcpp/" target="_blank">Download and Install WCPP from Neodynamic website</a><br />
                  </p>
                  <h3>#2 After installing WCPP...</h3>
                  <p>
                      <a href="#" onclick="javascript:$('#wcppDetection').hide();$('#printSection').show();">You can go and test the printing page...</a>
                  </p>
  
                  <script type="text/javascript">
  
                      var wcppPingTimeout_ms = 60000; //60 sec
                      var wcppPingTimeoutStep_ms = 500; //0.5 sec
  
                      function wcppDetectOnSuccess() {
                          // WCPP utility is installed at the client side
                          // redirect to WebClientPrint sample page
  
                          // get WCPP version
                          var wcppVer = arguments[0];
                          if (wcppVer.substring(0, 1) == "6"){
                              $('#wcppDetection').hide();
                              $('#printSection').show();
                          }   
                          else //force to install WCPP v6.0
                              wcppDetectOnFailure();
                      }
  
                      function wcppDetectOnFailure() {
                          // It seems WCPP is not installed at the client side
                          // ask the user to install it
                          $('#msgInProgress').hide();
                          $('#msgInstallWCPP').show();
                      }
  
                  </script>
  
              </div>
              
              <input type="hidden" id="sid" name="sid" ng-value="sid" />
              <script>
                  $(function () {
                      //Gen script for WCPP detection
                      $.getScript('/WebClientPrintAPI/ProcessRequest?d=' + $('#sid').val());
                  });
              </script>
  
          </div>
  
          <div id="printSection" style="display:none;">
              <h3>Print EPL commands</h3>
  
              <div>
                  <label class="checkbox">
                      <input type="checkbox" id="useDefaultPrinter" /> <strong>Print to Default printer</strong> or...
                  </label>
              </div>
  
              <div id="loadPrinters">
                  Click to load and select one of the installed printers!
                  <br />
                  <input type="button" onclick="javascript:jsWebClientPrint.getPrinters();" value="Load installed printers..." />
                  <br /><br />
              </div>
  
              <div id="installedPrinters" style="visibility:hidden">
                  <label for="installedPrinterName">Select an installed Printer:</label>
                  <select name="installedPrinterName" id="installedPrinterName"></select>
              </div>
  
              <script type="text/javascript">
  	            var wcppGetPrintersTimeout_ms = 60000; //60 sec
                  var wcppGetPrintersTimeoutStep_ms = 500; //0.5 sec 
  
  	            function wcpGetPrintersOnSuccess() {
  		            // Display client installed printers
  		            if (arguments[0].length > 0) {
  			            var p = arguments[0].split("|");
  			            var options = '';
  			            for (var i = 0; i < p.length; i++) {
  				            options += '<option>' + p[i] + '</option>';
  			            }
  			            $('#installedPrinters').css('visibility', 'visible');
  			            $('#installedPrinterName').html(options);
  			            $('#installedPrinterName').focus();
  			            $('#loadPrinters').hide();
  		            } else {
  			            alert("No printers are installed in your system.");
  		            }
  	            }
  	            function wcpGetPrintersOnFailure() {
  		            // Do something if printers cannot be got from the client
  		            alert("No printers are installed in your system.");
  	            }
              </script>
  
              <br />
  
              <input type="button" style="font-size:18px" onclick="javascript:jsWebClientPrint.print('useDefaultPrinter=' + $('#useDefaultPrinter').attr('checked') + '&printerName=' + $('#installedPrinterName').val());" value="Print EPL..." />
  
              <script>
                  $(function () {
                      // Create Base64 Object
                      var Base64 = { _keyStr: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=", encode: function (e) { var t = ""; var n, r, i, s, o, u, a; var f = 0; e = Base64._utf8_encode(e); while (f < e.length) { n = e.charCodeAt(f++); r = e.charCodeAt(f++); i = e.charCodeAt(f++); s = n >> 2; o = (n & 3) << 4 | r >> 4; u = (r & 15) << 2 | i >> 6; a = i & 63; if (isNaN(r)) { u = a = 64 } else if (isNaN(i)) { a = 64 } t = t + this._keyStr.charAt(s) + this._keyStr.charAt(o) + this._keyStr.charAt(u) + this._keyStr.charAt(a) } return t }, _utf8_encode: function (e) { e = e.replace(/\r\n/g, "\n"); var t = ""; for (var n = 0; n < e.length; n++) { var r = e.charCodeAt(n); if (r < 128) { t += String.fromCharCode(r) } else if (r > 127 && r < 2048) { t += String.fromCharCode(r >> 6 | 192); t += String.fromCharCode(r & 63 | 128) } else { t += String.fromCharCode(r >> 12 | 224); t += String.fromCharCode(r >> 6 & 63 | 128); t += String.fromCharCode(r & 63 | 128) } } return t } }
  
                      // Creat script for client side printing
                      var rootUrl = $(location).attr('protocol') + "//" + $(location).attr('host');
                      var ABSOLUTE_URL_TO_PRINT_JOB_CONTROLLER = rootUrl + '/PrintEPL/PrintCommands';
                      $.getScript('/WebClientPrintAPI/ProcessRequest?v6.0.0.0&' + new Date().getTime() + '&sid=' + $('#sid').val() + '&u=' + Base64.encode(ABSOLUTE_URL_TO_PRINT_JOB_CONTROLLER));
                      
                  });
              </script>
  
  
          </div>
      </div>
  
      <script>
          var app = angular.module('myApp', []);
          app.controller('myCtrl', function($scope) {
              $scope.sid = new Date().getTime();
          });
      </script>
  </body>
  </html>
  
  

  Creating HTTP Handlers

  Create a new Generic Handler and name it WebClientPrintAPI and then copy/paste the following code:

  
  public class WebClientPrintAPI : IHttpHandler {
   
      //*********************************
      // IMPORTANT NOTE 
      // In this sample we store users related stuff (like
      // the list of printers and whether they have the WCPP 
      // client utility installed) in the Application cache
      // object part of ASP.NET BUT you can change it to 
      // another different storage (like a DB or file server)!
      // which will be required in Load Balacing scenarios
      //*********************************
   
      public void ProcessRequest (HttpContext context) {
          //get session ID
          string sessionID = (context.Request["sid"] != null) ? context.Request["sid"].ToString() : null;
   
          //get Query String
          string queryString = context.Request.Url.Query;
   
          try
          {
              //Determine and get the Type of Request 
              RequestType prType = WebClientPrint.GetProcessRequestType(queryString);
   
              if (prType == RequestType.GenPrintScript ||
                  prType == RequestType.GenWcppDetectScript)
              {
                  //Let WebClientPrint to generate the requested script
                  byte[] script = WebClientPrint.GenerateScript(context.Request.Url.AbsoluteUri.Replace(queryString, ""), queryString);
   
                  context.Response.ContentType = "text/javascript";
                  context.Response.BinaryWrite(script);
              }
              else if (prType == RequestType.ClientSetWcppVersion)
              {
                  //This request is a ping from the WCPP utility
                  //so store the session ID indicating this user has the WCPP installed
                  //also store the WCPP Version if available
                  string wcppVersion = context.Request["wcppVer"];
                  if (string.IsNullOrEmpty(wcppVersion))
                      wcppVersion = "1.0.0.0";
   
                  context.Application.Set(sessionID + "wcppInstalled", wcppVersion);
              }
              else if (prType == RequestType.ClientSetInstalledPrinters)
              {
                  //WCPP Utility is sending the installed printers at client side
                  //so store this info with the specified session ID
                  string printers = context.Request["printers"];
                  if (string.IsNullOrEmpty(printers) == false)
                      printers = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printers));
   
                  context.Application.Set(sessionID + "printers", printers);
   
              }
              else if (prType == RequestType.ClientSetInstalledPrintersInfo)
              {
                  //WCPP Utility is sending the client installed printers with detailed info
                  //so store this info with the specified session ID
                  //Printers Info is in JSON format
                  string printersInfo = context.Request.Form["printersInfoContent"];
   
                  if (string.IsNullOrEmpty(printersInfo) == false)
                      printersInfo = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printersInfo));
   
                  context.Application.Set(sessionID + "printersInfo", printersInfo);
   
              }
              else if (prType == RequestType.ClientGetWcppVersion)
              {
                  //return the WCPP version for the specified Session ID (sid) if any
                  bool sidWcppVersion = (context.Application[sessionID + "wcppInstalled"] != null);
   
                  context.Response.ContentType = "text/plain";
                  context.Response.Write(sidWcppVersion ? context.Application[sessionID + "wcppInstalled"] : "");
   
              }
              else if (prType == RequestType.ClientGetInstalledPrinters)
              {
                  //return the installed printers for the specified Session ID (sid) if any
                  bool sidHasPrinters = (context.Application[sessionID + "printers"] != null);
   
                  context.Response.ContentType = "text/plain";
                  context.Response.Write(sidHasPrinters ? context.Application[sessionID + "printers"] : "");
   
              }
              else if (prType == RequestType.ClientGetInstalledPrintersInfo)
              {
                  //return the installed printers with detailed info for the specified Session ID (sid) if any
                  bool sidHasPrinters = (context.Application[sessionID + "printersInfo"] != null);
   
                  context.Response.ContentType = "text/plain";
                  context.Response.Write(sidHasPrinters ? context.Application[sessionID + "printersInfo"] : "");
   
              }
   
          }
          catch (Exception ex)
          {
              context.Response.StatusCode = 500;
              context.Response.ContentType = "text/plain";
              context.Response.Write(ex.Message + " - " + ex.StackTrace);
          }
   
   
   
      }
   
      public bool IsReusable {
          get {
              return false;
          }
      }
   
  }
  

  Create a new Generic Handler and name it PrintEPLHandler and then copy/paste the following code:

  
  <%@ WebHandler Language="C#" Class="PrintEPLHandler" %>
  
  using System;
  using System.Web;
  
  using Neodynamic.SDK.Web;
  
  public class PrintEPLHandler : IHttpHandler {
      
      /*############### IMPORTANT!!! ############
      If your website requires AUTHENTICATION, then you MUST configure THIS Handler file
      to be ANONYMOUS access allowed!!!
        ######################################### */
  
      public void ProcessRequest (HttpContext context) {
  
          if (WebClientPrint.ProcessPrintJob(context.Request.Url.Query))
          {
              bool useDefaultPrinter = (context.Request["useDefaultPrinter"] == "checked");
              string printerName = context.Server.UrlDecode(context.Request["printerName"]);
  
              //Create Zebra EPL commands for sample receipt
              
              string lineFeed = "0x0A";
  
              string cmds =  "";
              cmds += lineFeed;
              cmds += "N";
              cmds += lineFeed;
              cmds += "Q609,24";
              cmds += lineFeed;
              cmds += "q784";
              cmds += lineFeed;
              cmds += "A170,5,0,1,5,5,N,\"WORLDWIDE\"";
              cmds += lineFeed;
              cmds += "LO5,230,765,10";
              cmds += lineFeed;
              cmds += "A10,265,0,1,3,3,R,\"MODEL:\"";
              cmds += lineFeed;
              cmds += "A280,265,0,1,3,3,N,\"Bar Code Printer\"";
              cmds += lineFeed;
              cmds += "A10,340,0,1,3,3,R,\" CODE: \"";
              cmds += lineFeed;
              cmds += "B280,340,0,3C,2,6,120,B,\"BCP-1234\"";
              cmds += lineFeed;
              cmds += "LO5,520,765,10";
              cmds += lineFeed;
              cmds += "A100,550,0,1,2,2,N,\"ISO 9000 Made In USA\"";
              cmds += lineFeed;
              cmds += "P1";
              cmds += lineFeed;
  
  		    //Create a ClientPrintJob and send it back to the client!
  		    ClientPrintJob cpj = new ClientPrintJob();
  		    //set Zebra EPL commands to print...
  		    cpj.PrinterCommands = cmds;
  		    cpj.FormatHexValues = true;
  
  		    //set client printer...
  		    if (useDefaultPrinter || printerName == "null")
  			    cpj.ClientPrinter = new DefaultPrinter();
  		    else
  			    cpj.ClientPrinter = new InstalledPrinter(printerName);
  		
  		    //send it...		    
              context.Response.ContentType = "application/octet-stream";
              context.Response.BinaryWrite(cpj.GetContent());
              context.Response.End();
              
          }
          
      }
   
      public bool IsReusable {
          get {
              return false;
          }
      }
  
  }
  

  Creating/Editing WebForm Pages

  Be sure ALL *.aspx link to jQuery 1.4.1+ file!

  The default page is for detecting whether the client machine has the WebClientPrint Processor (WCPP) Utility installed. Edit the Default.aspx file and copy/paste the following code inside the BODY:

  
  
  <div id="msgInProgress">
      <div id="mySpinner" style="width:32px;height:32px"></div>
      <br />
      <h3>Detecting WCPP utility at client side...</h3>
      <h3>Please wait a few seconds...</h3>
      <br />
  </div>
  <div id="msgInstallWCPP" style="display:none;">
      <h3>#1 Install WebClientPrint Processor (WCPP)!</h3>
      <p>
          <strong>WCPP is a native app (without any dependencies!)</strong> that handles all print jobs
          generated by the <strong>WebClientPrint for ASP.NET component</strong> at the server side. The WCPP
          is in charge of the whole printing process and can be
          installed on <strong>Windows, Linux, Mac & Raspberry Pi!</strong>
      </p>
      <p>
          <a href="//www.neodynamic.com/downloads/wcpp/" target="_blank" >Download and Install WCPP from Neodynamic website</a><br />
      </p>
      <h3>#2 After installing WCPP...</h3>
      <p>
          <a href="PrintEPL.aspx" >You can go and test the printing page...</a>
      </p>
  
  </div>
  
      
  <script type="text/javascript">
  
      var wcppPingTimeout_ms = 60000; //60 sec
      var wcppPingTimeoutStep_ms = 500; //0.5 sec
                       
      function wcppDetectOnSuccess(){
          // WCPP utility is installed at the client side
          // redirect to WebClientPrint sample page
                  
          // get WCPP version
          var wcppVer = arguments[0];
          if(wcppVer.substring(0, 1) == "6")
              window.location.href = 'PrintEPL.aspx';
          else //force to install WCPP v6.0
              wcppDetectOnFailure();
      }
  
      function wcppDetectOnFailure() {
          // It seems WCPP is not installed at the client side
          // ask the user to install it
          $('#msgInProgress').hide();
          $('#msgInstallWCPP').show();
      }
  
  </script>
  
  
  <%-- WCPP detection script code --%>
  
  <%=Neodynamic.SDK.Web.WebClientPrint.CreateWcppDetectionScript(HttpContext.Current.Request.Url.Scheme + "://" + HttpContext.Current.Request.Url.Host + ":" + HttpContext.Current.Request.Url.Port + "/WebClientPrintAPI.ashx", HttpContext.Current.Session.SessionID)%>
  
  

  Add a new page and name it PrintEPL.aspx. Copy/paste the following code inside the BODY:

  
  <h3>Print EPL commands</h3>
  
  <div>
  <label class="checkbox">
  	<input type="checkbox" id="useDefaultPrinter" /> <strong>Print to Default printer</strong> or...
  </label>
  </div>
  
  <div id="loadPrinters">
  	Click to load and select one of the installed printers!
  	<br />
  	 <input type="button" onclick="javascript:jsWebClientPrint.getPrinters();" value="Load installed printers..." />
  	<br /><br />
  </div>
  
  <div id="installedPrinters" style="visibility:hidden">
  	<label for="installedPrinterName">Select an installed Printer:</label>
  	<select name="installedPrinterName" id="installedPrinterName"></select>
  </div>
  
  <script type="text/javascript">
  	var wcppGetPrintersTimeout_ms = 60000; //60 sec
      var wcppGetPrintersTimeoutStep_ms = 500; //0.5 sec
  
  	function wcpGetPrintersOnSuccess() {
  		// Display client installed printers
  		if (arguments[0].length > 0) {
  			var p = arguments[0].split("|");
  			var options = '';
  			for (var i = 0; i < p.length; i++) {
  				options += '<option>' + p[i] + '</option>';
  			}
  			$('#installedPrinters').css('visibility', 'visible');
  			$('#installedPrinterName').html(options);
  			$('#installedPrinterName').focus();
  			$('#loadPrinters').hide();
  		} else {
  			alert("No printers are installed in your system.");
  		}
  	}
  	function wcpGetPrintersOnFailure() {
  		// Do something if printers cannot be got from the client
  		alert("No printers are installed in your system.");
  	}
  </script>
  
  <br />
  
  <input type="button" style="font-size:18px" onclick="javascript:jsWebClientPrint.print('useDefaultPrinter=' + $('#useDefaultPrinter').attr('checked') + '&printerName=' + $('#installedPrinterName').val());" value="Print EPL..." />
  
  <%-- Register the WebClientPrint script code --%>
  
  <%=Neodynamic.SDK.Web.WebClientPrint.CreateScript(HttpContext.Current.Request.Url.Scheme + "://" + HttpContext.Current.Request.Url.Host + ":" + HttpContext.Current.Request.Url.Port + "/WebClientPrintAPI.ashx", HttpContext.Current.Request.Url.Scheme + "://" + HttpContext.Current.Request.Url.Host + ":" + HttpContext.Current.Request.Url.Port + "/PrintEPLHandler.ashx", HttpContext.Current.Session.SessionID)%>
  
  

  Creating HTTP Handlers

  Create a new Generic Handler and name it WebClientPrintAPI and then copy/paste the following code:

  
  <%@ WebHandler Language="VB" Class="WebClientPrintAPI" %>
  
  Imports System
  Imports System.Web
   
  Imports Neodynamic.SDK.Web
   
   
  Public Class WebClientPrintAPI : Implements IHttpHandler
   
      '*********************************
      ' IMPORTANT NOTE 
      ' In this sample we store users related stuff (like
      ' the list of printers and whether they have the WCPP 
      ' client utility installed) in the Application cache
      ' object part of ASP.NET BUT you can change it to 
      ' another different storage (like a DB or file server)!
      ' which will be required in Load Balacing scenarios
      '*********************************
   
      Public Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
          'get session ID
          Dim sessionID As String = ""
          If (context.Request("sid") IsNot Nothing) Then
              sessionID = context.Request("sid")
          End If
   
          'get Query String
          Dim queryString As String = context.Request.Url.Query
   
          Try
              'Determine and get the Type of Request 
              Dim prType As RequestType = WebClientPrint.GetProcessRequestType(queryString)
   
              If prType = RequestType.GenPrintScript OrElse prType = RequestType.GenWcppDetectScript Then
                  'Let WebClientPrint to generate the requested script
                  Dim script As Byte() = WebClientPrint.GenerateScript(context.Request.Url.AbsoluteUri.Replace(queryString, ""), queryString)
   
                  context.Response.ContentType = "text/javascript"
                  context.Response.BinaryWrite(script)
              ElseIf prType = RequestType.ClientSetWcppVersion Then
                  'This request is a ping from the WCPP utility
                  'so store the session ID indicating this user has the WCPP installed
                  'also store the WCPP Version if available
                  Dim wcppVersion As String = context.Request("wcppVer")
                  If String.IsNullOrEmpty(wcppVersion) Then
                      wcppVersion = "1.0.0.0"
                  End If
   
                  context.Application.Set(sessionID & "wcppInstalled", wcppVersion)
              ElseIf prType = RequestType.ClientSetInstalledPrinters Then
                  'WCPP Utility is sending the installed printers at client side
                  'so store this info with the specified session ID
                  Dim printers As String = context.Request("printers")
                  If Not String.IsNullOrEmpty(printers) Then
                      printers = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printers))
                  End If
   
                  context.Application.Set(sessionID & "printers", printers)
   
              ElseIf prType = RequestType.ClientSetInstalledPrintersInfo Then
                  'WCPP Utility is sending the installed printers at client side
                  'so store this info with the specified session ID
                  'Printers Info is in JSON format
                  Dim printersInfo As String = context.Request.Form("printersInfoContent")
                  If Not String.IsNullOrEmpty(printersInfo) Then
                      printersInfo = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(printersInfo))
                  End If
   
                  context.Application.Set(sessionID & "printersInfo", printersInfo)
   
              ElseIf prType = RequestType.ClientGetWcppVersion Then
                  'return the WCPP version for the specified Session ID (sid) if any
                  Dim sidWcppVersion As Boolean = (context.Application(sessionID & "wcppInstalled") IsNot Nothing)
   
                  context.Response.ContentType = "text/plain"
                  If (sidWcppVersion) Then
                      context.Response.Write(context.Application(sessionID & "wcppInstalled").ToString())
                  End If
   
              ElseIf prType = RequestType.ClientGetInstalledPrinters Then
                  'return the installed printers for the specified Session ID (sid) if any
                  Dim sidHasPrinters As Boolean = (context.Application(sessionID & "printers") IsNot Nothing)
   
                  context.Response.ContentType = "text/plain"
   
                  If (sidHasPrinters) Then
                      context.Response.Write(context.Application(sessionID & "printers").ToString())
                  End If
   
              ElseIf prType = RequestType.ClientGetInstalledPrintersInfo Then
                  'return the installed printers with detailed info for the specified Session ID (sid) if any
                  Dim sidHasPrinters As Boolean = (context.Application(sessionID & "printersInfo") IsNot Nothing)
   
                  context.Response.ContentType = "text/plain"
   
                  If (sidHasPrinters) Then
                      context.Response.Write(context.Application(sessionID & "printersInfo").ToString())
                  End If
              End If
          Catch ex As Exception
              context.Response.StatusCode = 500
              context.Response.ContentType = "text/plain"
              context.Response.Write(ex.Message + " - " + ex.StackTrace)
          End Try
   
   
   
      End Sub
   
   
      Public ReadOnly Property IsReusable() As Boolean Implements IHttpHandler.IsReusable
          Get
              Return False
          End Get
      End Property
   
  End Class
  

  Create a new Generic Handler and name it PrintEPLHandler and then copy/paste the following code:

  
  <%@ WebHandler Language="VB" Class="PrintEPLHandler" %>
  
  Imports System
  Imports System.Web
  
  Imports Neodynamic.SDK.Web
  
  Public Class PrintEPLHandler : Implements IHttpHandler
  
  
      '############### IMPORTANT!!! ############
      ' If your website requires AUTHENTICATION, then you MUST configure THIS Handler file
      ' to be ANONYMOUS access allowed!!!
      '######################################### 
  
  
      Public Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
  
          If WebClientPrint.ProcessPrintJob(context.Request.Url.Query) Then
              Dim useDefaultPrinter As Boolean = (context.Request("useDefaultPrinter") = "checked")
              Dim printerName As String = context.Server.UrlDecode(context.Request("printerName"))
  
              'Create Zebra EPL commands for sample label
  
              Dim lineFeed As String = "0x0A"
  
              Dim cmds As String
              cmds += lineFeed
              cmds += "N"
              cmds += lineFeed
              cmds += "Q609,24"
              cmds += lineFeed
              cmds += "q784"
              cmds += lineFeed
              cmds += "A170,5,0,1,5,5,N,""WORLDWIDE"""
              cmds += lineFeed
              cmds += "LO5,230,765,10"
              cmds += lineFeed
              cmds += "A10,265,0,1,3,3,R,""MODEL:"""
              cmds += lineFeed
              cmds += "A280,265,0,1,3,3,N,""Bar Code Printer"""
              cmds += lineFeed
              cmds += "A10,340,0,1,3,3,R,"" CODE: """
              cmds += lineFeed
              cmds += "B280,340,0,3C,2,6,120,B,""BCP-1234"""
              cmds += lineFeed
              cmds += "LO5,520,765,10"
              cmds += lineFeed
              cmds += "A100,550,0,1,2,2,N,""ISO 9000 Made In USA"""
              cmds += lineFeed
              cmds += "P1"
              cmds += lineFeed
  
  		    'Create a ClientPrintJob and send it back to the client!
  		    Dim cpj As New ClientPrintJob()
  		    'set Zebra EPL commands to print...
  		    cpj.PrinterCommands = cmds
  		    cpj.FormatHexValues = True
  
              Dim cpj As New ClientPrintJob()
              cpj.PrintFile = file
              If useDefaultPrinter OrElse printerName = "null" Then
                  cpj.ClientPrinter = New DefaultPrinter()
              Else
                  cpj.ClientPrinter = New InstalledPrinter(printerName)
              End If
  
              context.Response.ContentType = "application/octet-stream"
              context.Response.BinaryWrite(cpj.GetContent())
              context.Response.End()
              
          End If
  
      End Sub
  
  
      Public ReadOnly Property IsReusable() As Boolean Implements IHttpHandler.IsReusable
          Get
              Return False
          End Get
      End Property
  
  End Class
  

  Creating/Editing WebForm Pages

  Be sure ALL *.aspx link to jQuery 1.4.1+ file!

  The default page is for detecting whether the client machine has the WebClientPrint Processor (WCPP) Utility installed. Edit the Default.aspx file and copy/paste the following code inside the BODY:

  
  
  <div id="msgInProgress">
      <div id="mySpinner" style="width:32px;height:32px"></div>
      <br />
      <h3>Detecting WCPP utility at client side...</h3>
      <h3>Please wait a few seconds...</h3>
      <br />
  </div>
  <div id="msgInstallWCPP" style="display:none;">
      <h3>#1 Install WebClientPrint Processor (WCPP)!</h3>
      <p>
          <strong>WCPP is a native app (without any dependencies!)</strong> that handles all print jobs
          generated by the <strong>WebClientPrint for ASP.NET component</strong> at the server side. The WCPP
          is in charge of the whole printing process and can be
          installed on <strong>Windows, Linux, Mac & Raspberry Pi!</strong>
      </p>
      <p>
          <a href="//www.neodynamic.com/downloads/wcpp/" target="_blank" >Download and Install WCPP from Neodynamic website</a><br />
      </p>
      <h3>#2 After installing WCPP...</h3>
      <p>
          <a href="PrintEPL.aspx" >You can go and test the printing page...</a>
      </p>
  
  </div>
  
      
  <script type="text/javascript">
  
      var wcppPingTimeout_ms = 60000; //60 sec
      var wcppPingTimeoutStep_ms = 500; //0.5 sec
                   
      function wcppDetectOnSuccess(){
          // WCPP utility is installed at the client side
          // redirect to WebClientPrint sample page
                  
          // get WCPP version
          var wcppVer = arguments[0];
          if(wcppVer.substring(0, 1) == "6")
              window.location.href = 'PrintEPL.aspx';
          else //force to install WCPP v6.0
              wcppDetectOnFailure();
      }
  
      function wcppDetectOnFailure() {
          // It seems WCPP is not installed at the client side
          // ask the user to install it
          $('#msgInProgress').hide();
          $('#msgInstallWCPP').show();
      }
  
  </script>
  
  
  <%-- WCPP detection script code --%>
  
  <%=Neodynamic.SDK.Web.WebClientPrint.CreateWcppDetectionScript(HttpContext.Current.Request.Url.Scheme + "://" + HttpContext.Current.Request.Url.Host + ":" + HttpContext.Current.Request.Url.Port + "/WebClientPrintAPI.ashx", HttpContext.Current.Session.SessionID)%>
  
  

  Add a new page and name it PrintEPL.aspx. Copy/paste the following code inside the BODY:

  
  <h3>Print EPL commands</h3>
  
  <div>
  <label class="checkbox">
  	<input type="checkbox" id="useDefaultPrinter" /> <strong>Print to Default printer</strong> or...
  </label>
  </div>
  
  <div id="loadPrinters">
  	Click to load and select one of the installed printers!
  	<br />
  	 <input type="button" onclick="javascript:jsWebClientPrint.getPrinters();" value="Load installed printers..." />
  	<br /><br />
  </div>
  
  <div id="installedPrinters" style="visibility:hidden">
  	<label for="installedPrinterName">Select an installed Printer:</label>
  	<select name="installedPrinterName" id="installedPrinterName"></select>
  </div>
  
  <script type="text/javascript">
  	var wcppGetPrintersTimeout_ms = 60000; //60 sec
      var wcppGetPrintersTimeoutStep_ms = 500; //0.5 sec
  
  	function wcpGetPrintersOnSuccess() {
  		// Display client installed printers
  		if (arguments[0].length > 0) {
  			var p = arguments[0].split("|");
  			var options = '';
  			for (var i = 0; i < p.length; i++) {
  				options += '<option>' + p[i] + '</option>';
  			}
  			$('#installedPrinters').css('visibility', 'visible');
  			$('#installedPrinterName').html(options);
  			$('#installedPrinterName').focus();
  			$('#loadPrinters').hide();
  		} else {
  			alert("No printers are installed in your system.");
  		}
  	}
  	function wcpGetPrintersOnFailure() {
  		// Do something if printers cannot be got from the client
  		alert("No printers are installed in your system.");
  	}
  </script>
  
  <br />
  
  <input type="button" style="font-size:18px" onclick="javascript:jsWebClientPrint.print('useDefaultPrinter=' + $('#useDefaultPrinter').attr('checked') + '&printerName=' + $('#installedPrinterName').val());" value="Print EPL..." />
  
  <%-- Register the WebClientPrint script code --%>
  
  <%=Neodynamic.SDK.Web.WebClientPrint.CreateScript(HttpContext.Current.Request.Url.Scheme + "://" + HttpContext.Current.Request.Url.Host + ":" + HttpContext.Current.Request.Url.Port + "/WebClientPrintAPI.ashx", HttpContext.Current.Request.Url.Scheme + "://" + HttpContext.Current.Request.Url.Host + ":" + HttpContext.Current.Request.Url.Port + "/PrintEPLHandler.ashx", HttpContext.Current.Session.SessionID)%>
  
  

• That's it! Run your website and test it. Click on Print EPL to print the Zebra EPL Commands without print dialog. You can print it to the Default client printer or you can get a list of the installed printers available at the client machine.
  
  
  NOTE You can also print directly to any LPT Parallel Port, RS232 Serial Port or IP/Ethernet Printer although these scenarios have not been considered in this article for simplicity. For further details on those scenarios, please contact our tech support.