Gửi dữ liệu đến máy in USB trong C#?

Question

Tôi có mã script cho máy in zebra TLP2844 trong một tệp văn bản. Tôi cần in tập lệnh đó vào máy in được kết nối qua USB. Tôi đã thực thi tập lệnh đó bằng cổng song song bằng cách sử dụng lệnh DOS:

/c type filename.txt >PRN 

Nhưng máy in được kết nối với USB. Làm cách nào để gửi lệnh in tới usb? Tôi có nên sử dụng lớp printdocument không?

Answer 1

Microsoft có mẫu này mã có sẵn để sử dụng:

How to send raw data to a printer by using Visual C# .NET

using System; 
using System.Drawing; 
using System.Drawing.Printing; 
using System.IO; 
using System.Runtime.InteropServices; 
using System.Windows.Forms; 

public class RawPrinterHelper 
{ 
    // Structure and API declarions: 
    [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Ansi)] 
    public class DOCINFOA 
    { 
    [MarshalAs(UnmanagedType.LPStr)] public string pDocName; 
    [MarshalAs(UnmanagedType.LPStr)] public string pOutputFile; 
    [MarshalAs(UnmanagedType.LPStr)] public string pDataType; 
    } 
    [DllImport("winspool.Drv", EntryPoint="OpenPrinterA", SetLastError=true, CharSet=CharSet.Ansi, ExactSpelling=true, CallingConvention=CallingConvention.StdCall)] 
    public static extern bool OpenPrinter([MarshalAs(UnmanagedType.LPStr)] string szPrinter, out IntPtr hPrinter, IntPtr pd); 

    [DllImport("winspool.Drv", EntryPoint="ClosePrinter", SetLastError=true, ExactSpelling=true, CallingConvention=CallingConvention.StdCall)] 
    public static extern bool ClosePrinter(IntPtr hPrinter); 

    [DllImport("winspool.Drv", EntryPoint="StartDocPrinterA", SetLastError=true, CharSet=CharSet.Ansi, ExactSpelling=true, CallingConvention=CallingConvention.StdCall)] 
    public static extern bool StartDocPrinter(IntPtr hPrinter, Int32 level, [In, MarshalAs(UnmanagedType.LPStruct)] DOCINFOA di); 

    [DllImport("winspool.Drv", EntryPoint="EndDocPrinter", SetLastError=true, ExactSpelling=true, CallingConvention=CallingConvention.StdCall)] 
    public static extern bool EndDocPrinter(IntPtr hPrinter); 

    [DllImport("winspool.Drv", EntryPoint="StartPagePrinter", SetLastError=true, ExactSpelling=true, CallingConvention=CallingConvention.StdCall)] 
    public static extern bool StartPagePrinter(IntPtr hPrinter); 

    [DllImport("winspool.Drv", EntryPoint="EndPagePrinter", SetLastError=true, ExactSpelling=true, CallingConvention=CallingConvention.StdCall)] 
    public static extern bool EndPagePrinter(IntPtr hPrinter); 

    [DllImport("winspool.Drv", EntryPoint="WritePrinter", SetLastError=true, ExactSpelling=true, CallingConvention=CallingConvention.StdCall)] 
    public static extern bool WritePrinter(IntPtr hPrinter, IntPtr pBytes, Int32 dwCount, out Int32 dwWritten); 

    // SendBytesToPrinter() 
    // When the function is given a printer name and an unmanaged array 
    // of bytes, the function sends those bytes to the print queue. 
    // Returns true on success, false on failure. 
    public static bool SendBytesToPrinter(string szPrinterName, IntPtr pBytes, Int32 dwCount) 
    { 
    Int32 dwError = 0, dwWritten = 0; 
    IntPtr hPrinter = new IntPtr(0); 
    DOCINFOA di = new DOCINFOA(); 
    bool bSuccess = false; // Assume failure unless you specifically succeed. 
    di.pDocName = "My C#.NET RAW Document"; 
    di.pDataType = "RAW"; 

    // Open the printer. 
    if(OpenPrinter(szPrinterName.Normalize(), out hPrinter, IntPtr.Zero)) 
    { 
     // Start a document. 
     if(StartDocPrinter(hPrinter, 1, di)) 
     { 
     // Start a page. 
     if(StartPagePrinter(hPrinter)) 
     { 
      // Write your bytes. 
      bSuccess = WritePrinter(hPrinter, pBytes, dwCount, out dwWritten); 
      EndPagePrinter(hPrinter); 
     } 
     EndDocPrinter(hPrinter); 
     } 
     ClosePrinter(hPrinter); 
    } 
    // If you did not succeed, GetLastError may give more information 
    // about why not. 
    if(bSuccess == false) 
    { 
     dwError = Marshal.GetLastWin32Error(); 
    } 
    return bSuccess; 
    } 

    public static bool SendFileToPrinter(string szPrinterName, string szFileName) 
    { 
    // Open the file. 
    FileStream fs = new FileStream(szFileName, FileMode.Open); 
    // Create a BinaryReader on the file. 
    BinaryReader br = new BinaryReader(fs); 
    // Dim an array of bytes big enough to hold the file's contents. 
    Byte []bytes = new Byte[fs.Length]; 
    bool bSuccess = false; 
    // Your unmanaged pointer. 
    IntPtr pUnmanagedBytes = new IntPtr(0); 
    int nLength; 

    nLength = Convert.ToInt32(fs.Length); 
    // Read the contents of the file into the array. 
    bytes = br.ReadBytes(nLength); 
    // Allocate some unmanaged memory for those bytes. 
    pUnmanagedBytes = Marshal.AllocCoTaskMem(nLength); 
    // Copy the managed byte array into the unmanaged array. 
    Marshal.Copy(bytes, 0, pUnmanagedBytes, nLength); 
    // Send the unmanaged bytes to the printer. 
    bSuccess = SendBytesToPrinter(szPrinterName, pUnmanagedBytes, nLength); 
    // Free the unmanaged memory that you allocated earlier. 
    Marshal.FreeCoTaskMem(pUnmanagedBytes); 
    return bSuccess; 
    } 

    public static bool SendStringToPrinter(string szPrinterName, string szString) 
    { 
    IntPtr pBytes; 
    Int32 dwCount; 

    // How many characters are in the string? 
    // Fix from Nicholas Piasecki: 
    // dwCount = szString.Length; 
    dwCount = (szString.Length + 1) * Marshal.SystemMaxDBCSCharSize; 

    // Assume that the printer is expecting ANSI text, and then convert 
    // the string to ANSI text. 
    pBytes = Marshal.StringToCoTaskMemAnsi(szString); 
    // Send the converted ANSI string to the printer. 
    SendBytesToPrinter(szPrinterName, pBytes, dwCount); 
    Marshal.FreeCoTaskMem(pBytes); 
    return true; 
    } 
} 

Bao gồm bản vá lỗi từ Nicholas Piasecki

Answer 2

Bạn cũng có thể làm một share/chụp của máy in như LPT và sau đó bạn có thể in qua lệnh loại.

http://www.nrgsoft.com/support/activekb/questions.php?questionid=11

Answer 3

Nó làm việc cho tôi!

public partial class USB : Form 
{ 
    public USB() 
    { 
     InitializeComponent(); 
    } 


    // Structure and API declarions: 
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)] 
    public class DOCINFOA 
    { 
     [MarshalAs(UnmanagedType.LPStr)] 
     public string pDocName; 
     [MarshalAs(UnmanagedType.LPStr)] 
     public string pOutputFile; 
     [MarshalAs(UnmanagedType.LPStr)] 
     public string pDataType; 
    } 
    [DllImport("winspool.Drv", EntryPoint = "OpenPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)] 
    public static extern bool OpenPrinter([MarshalAs(UnmanagedType.LPStr)] string szPrinter, out IntPtr hPrinter, IntPtr pd); 

    [DllImport("winspool.Drv", EntryPoint = "ClosePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)] 
    public static extern bool ClosePrinter(IntPtr hPrinter); 

    [DllImport("winspool.Drv", EntryPoint = "StartDocPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)] 
    public static extern bool StartDocPrinter(IntPtr hPrinter, Int32 level, [In, MarshalAs(UnmanagedType.LPStruct)] DOCINFOA di); 

    [DllImport("winspool.Drv", EntryPoint = "EndDocPrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)] 
    public static extern bool EndDocPrinter(IntPtr hPrinter); 

    [DllImport("winspool.Drv", EntryPoint = "StartPagePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)] 
    public static extern bool StartPagePrinter(IntPtr hPrinter); 

    [DllImport("winspool.Drv", EntryPoint = "EndPagePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)] 
    public static extern bool EndPagePrinter(IntPtr hPrinter); 

    [DllImport("winspool.Drv", EntryPoint = "WritePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)] 
    public static extern bool WritePrinter(IntPtr hPrinter, IntPtr pBytes, Int32 dwCount, out Int32 dwWritten); 

    // SendBytesToPrinter() 
    // When the function is given a printer name and an unmanaged array 
    // of bytes, the function sends those bytes to the print queue. 
    // Returns true on success, false on failure. 
    public static bool SendBytesToPrinter(string szPrinterName, IntPtr pBytes, Int32 dwCount) 
    { 
     Int32 dwError = 0, dwWritten = 0; 
     IntPtr hPrinter = new IntPtr(0); 
     DOCINFOA di = new DOCINFOA(); 
     bool bSuccess = false; // Assume failure unless you specifically succeed. 
     di.pDocName = "My C#.NET RAW Document"; 
     di.pDataType = "RAW"; 

     // Open the printer. 
     if (OpenPrinter(szPrinterName.Normalize(), out hPrinter, IntPtr.Zero)) 
     { 
      // Start a document. 
      if (StartDocPrinter(hPrinter, 1, di)) 
      { 
       // Start a page. 
       if (StartPagePrinter(hPrinter)) 
       { 
        // Write your bytes. 
        bSuccess = WritePrinter(hPrinter, pBytes, dwCount, out dwWritten); 
        EndPagePrinter(hPrinter); 
       } 
       EndDocPrinter(hPrinter); 
      } 
      ClosePrinter(hPrinter); 
     } 
     // If you did not succeed, GetLastError may give more information 
     // about why not. 
     if (bSuccess == false) 
     { 
      dwError = Marshal.GetLastWin32Error(); 
     } 
     return bSuccess; 
    } 

    public static bool SendFileToPrinter(string szPrinterName, string szFileName) 
    { 
     // Open the file. 
     FileStream fs = new FileStream(szFileName, FileMode.Open); 
     // Create a BinaryReader on the file. 
     BinaryReader br = new BinaryReader(fs); 
     // Dim an array of bytes big enough to hold the file's contents. 
     Byte[] bytes = new Byte[fs.Length]; 
     bool bSuccess = false; 
     // Your unmanaged pointer. 
     IntPtr pUnmanagedBytes = new IntPtr(0); 
     int nLength; 

     nLength = Convert.ToInt32(fs.Length); 
     // Read the contents of the file into the array. 
     bytes = br.ReadBytes(nLength); 
     // Allocate some unmanaged memory for those bytes. 
     pUnmanagedBytes = Marshal.AllocCoTaskMem(nLength); 
     // Copy the managed byte array into the unmanaged array. 
     Marshal.Copy(bytes, 0, pUnmanagedBytes, nLength); 
     // Send the unmanaged bytes to the printer. 
     bSuccess = SendBytesToPrinter(szPrinterName, pUnmanagedBytes, nLength); 
     // Free the unmanaged memory that you allocated earlier. 
     Marshal.FreeCoTaskMem(pUnmanagedBytes); 
     return bSuccess; 
    } 

    public static bool SendStringToPrinter(string szPrinterName, string szString) 
    { 
     IntPtr pBytes; 
     Int32 dwCount; 

     // How many characters are in the string? 
     // Fix from Nicholas Piasecki: 
     // dwCount = szString.Length; 
     dwCount = (szString.Length + 1) * Marshal.SystemMaxDBCSCharSize; 

     // Assume that the printer is expecting ANSI text, and then convert 
     // the string to ANSI text. 
     pBytes = Marshal.StringToCoTaskMemAnsi(szString); 
     // Send the converted ANSI string to the printer. 
     SendBytesToPrinter(szPrinterName, pBytes, dwCount); 
     Marshal.FreeCoTaskMem(pBytes); 
     return true; 
    }  


    private void buttonSEND_Click(object sender, EventArgs e) 
    { 
     System.Windows.Forms.OpenFileDialog open = new System.Windows.Forms.OpenFileDialog(); 
     string dados = ""; 
     if (open.ShowDialog().Equals(DialogResult.OK)) 
     { 
      StreamReader sr = new StreamReader(open.FileName); 
      dados = sr.ReadToEnd(); 
      sr.Close(); 
     } 
     string printer = "PRINTER NAME"; 

     for (int i = 0; i < 30; i++) 
     { 
      SendStringToPrinter(printer, dados);  
     } 

    } 
}