How to send raw ZPL to Zebra printer using C # via USB

Question

I am a novice C # programmer. I have a project that requires me to send an unprocessed command to the Zebra LP 2844 printer via USB and make it work. I did a lot of research and tried to figure out how to do this. I am using the code http://support.microsoft.com/kb/322091 , but this did not work. Based on my test, it seems that I sent commands to the printer, but it did not respond and did not print. I have no idea about this. Can someone help me?

I use the button to send the command directly

private void button2_Click(object sender, EventArgs e) { string s = "A50,50,0,2,1,1,N,\"9129302\""; // Allow the user to select a printer. PrintDialog pd = new PrintDialog(); pd.PrinterSettings = new PrinterSettings(); if (DialogResult.OK == pd.ShowDialog(this)) { // Send a printer-specific to the printer. RawPrinterHelper.SendStringToPrinter(pd.PrinterSettings.PrinterName, s); MessageBox.Show("Data sent to printer."); } } 

Answer 1

EDIT . To address your update, the problem you are facing is to use SendStringToPrinter , which sends to the printer an ANSI string (zero terminated), which is not what the printer is expecting. According to the official

I did this with a Zebra language older than EPL2, but it should be very similar to what you need to do with ZPL. Perhaps this will help you get started in the right direction.

 public class Label { #region Print logic. Taken from http://support.microsoft.com/kb/322091 //Snip stuff unchanged from the KB example. [DllImport("winspool.Drv", EntryPoint="WritePrinter", SetLastError=true, ExactSpelling=true, CallingConvention=CallingConvention.StdCall)] public static extern bool WritePrinter(IntPtr hPrinter, byte[] pBytes, Int32 dwCount, out Int32 dwWritten ); private static bool SendBytesToPrinter(string szPrinterName, byte[] Bytes, Int32 dwCount) { Int32 dwError = 0, dwWritten = 0; IntPtr hPrinter = new IntPtr(0); DOCINFOA di = new DOCINFOA(); bool bSuccess = false; di.pDocName = "Zebra Label"; di.pDataType = "RAW"; if (OpenPrinter(szPrinterName.Normalize(), out hPrinter, IntPtr.Zero)) { if (StartDocPrinter(hPrinter, 1, di)) { if (StartPagePrinter(hPrinter)) { bSuccess = WritePrinter(hPrinter, Bytes, dwCount, out dwWritten); EndPagePrinter(hPrinter); } EndDocPrinter(hPrinter); } ClosePrinter(hPrinter); } if (bSuccess == false) { dwError = Marshal.GetLastWin32Error(); throw new Win32Exception(dwError); } return bSuccess; } #endregion public byte[] CreateCompleteCommand(bool headerAndFooter) { List<byte> byteCollection = new List<byte>(); //Static header content describing the label. if (headerAndFooter) { byteCollection.AddRange(Encoding.ASCII.GetBytes("\nN\n")); byteCollection.AddRange(Encoding.ASCII.GetBytes(String.Format("S{0}\n", this.Speed))); byteCollection.AddRange(Encoding.ASCII.GetBytes(String.Format("D{0}\n", this.Density))); byteCollection.AddRange(Encoding.ASCII.GetBytes(String.Format("q{0}\n", this.LabelHeight))); if (this.AdvancedLabelSizing) { byteCollection.AddRange(Encoding.ASCII.GetBytes(String.Format("Q{0},{1}\n", this.LableLength, this.GapLength))); } } //The content of the label. foreach (var command in this.Commands) { byteCollection.AddRange(command.GenerateByteCommand()); } //The footer content of the label. if(headerAndFooter) byteCollection.AddRange(Encoding.ASCII.GetBytes(String.Format("P{0}\n", this.Pages))); return byteCollection.ToArray(); } public bool PrintLabel(string printer) { byte[] command = this.CreateCompleteCommand(true); return SendBytesToPrinter(printer, command, command.Length); } public List<Epl2CommandBase> Commands { get; private set; } //Snip rest of the code. } public abstract partial class Epl2CommandBase { protected Epl2CommandBase() { } public virtual byte[] GenerateByteCommand() { return Encoding.ASCII.GetBytes(CommandString + '\n'); } public abstract string CommandString { get; set; } } public class Text : Epl2CommandBase { public override string CommandString { get { string printText = TextValue; if (Font == Fonts.Pts24) printText = TextValue.ToUpperInvariant(); printText = printText.Replace("\\", "\\\\"); // Replace \ with \\ printText = printText.Replace("\"", "\\\""); // replace " with \" return String.Format("A{0},{1},{2},{3},{4},{5},{6},\"{7}\"", X, Y, (byte)TextRotation, (byte)Font, HorziontalMultiplier, VertricalMultiplier, Reverse, printText); } set { GenerateCommandFromText(value); } } private void GenerateCommandFromText(string command) { if (!command.StartsWith(GetFactoryKey())) throw new ArgumentException("Command must begin with " + GetFactoryKey()); string[] commands = command.Substring(1).Split(','); this.X = int.Parse(commands[0]); this.Y = int.Parse(commands[1]); this.TextRotation = (Rotation)byte.Parse(commands[2]); this.Font = (Fonts)byte.Parse(commands[3]); this.HorziontalMultiplier = int.Parse(commands[4]); this.VertricalMultiplier = int.Parse(commands[5]); this.ReverseImageColor = commands[6].Trim().ToUpper() == "R"; string message = String.Join(",", commands, 7, commands.Length - 7); this.TextValue = message.Substring(1, message.Length - 2); // Remove the " at the beginning and end of the string. } //Snip }