Stampa su LPT1 in C #

Come si stampa direttamente su una stampante ad aghi in C # usando il file LPT1.

L’ho fatto su C ++ con fopen, ma non so come farlo in c #.

Grazie mille

Impostare la stampante in Windows come Generico / Solo testo, quindi stampare su di essa.

Ecco il codice che uso per stampare su una stampante di etichette che ha il proprio formato di testo codificato.

using System; using System.Collections.Generic; using System.Text; using System.Drawing; using System.Drawing.Printing; using System.Windows.Forms; using System.Runtime.InteropServices; using System.IO; namespace whatever { 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? dwCount = szString.Length; // 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. bool success = SendBytesToPrinter(szPrinterName, pBytes, dwCount); Marshal.FreeCoTaskMem(pBytes); return success; } } } 

Quindi questo viene chiamato da un’altra class come questa:

  private bool PrintLabels(string printerName) { return RawPrinterHelper.SendStringToPrinter(printerName, this.Text); } 

(modifica: se qualcuno vede dei principali fan collegati a risorse non gestite, fammi sapere nei commenti)

Forse non puoi stampare sul dispositivo “LPT1” ma su una “stupida stampante telescrivente” che devi installare prima. Se esistono nelle windows moderne …. Quindi dovresti stampare su “mydumbprinter” che a sua volta usa LPT1 come porta stampante. Mi è sembrato che seguissi il link Source di Cocowalla sopra: lì selezioni una stampante in un PrinterDialog. Il nome della stampante risultante sarebbe più probabilmente “Laserjet” che “LPT1”.

In C # è ansible, per prima cosa è necessario connettersi a quella porta usando il metodo CreateFile , quindi aprire un filestream su quella porta per scrivere definitivamente su di essa. Ecco una class di esempio che scrive due linee sulla stampante su LPT1 .

 using Microsoft.Win32.SafeHandles; using System; using System.IO; using System.Runtime.InteropServices; namespace YourNamespace { public static class Print2LPT { [DllImport("kernel32.dll", SetLastError = true)] static extern SafeFileHandle CreateFile(string lpFileName, FileAccess dwDesiredAccess,uint dwShareMode, IntPtr lpSecurityAttributes, FileMode dwCreationDisposition, uint dwFlagsAndAttributes, IntPtr hTemplateFile); public static bool Print() { string nl = Convert.ToChar(13).ToString() + Convert.ToChar(10).ToString(); bool IsConnected= false; string sampleText ="Hello World!" + nl + "Enjoy Printing..."; try { Byte[] buffer = new byte[sampleText.Length]; buffer = System.Text.Encoding.ASCII.GetBytes(sampleText); SafeFileHandle fh = CreateFile("LPT1:", FileAccess.Write, 0, IntPtr.Zero, FileMode.OpenOrCreate, 0, IntPtr.Zero); if (!fh.IsInvalid) { IsConnected= true; FileStream lpt1 = new FileStream(fh,FileAccess.ReadWrite); lpt1.Write(buffer, 0, buffer.Length); lpt1.Close(); } } catch (Exception ex) { string message = ex.Message; } return IsConnected; } } } 

Supponendo che la stampante sia collegata alla porta LPT1 , in caso contrario sarà necessario regolare il metodo CreateFile modo che corrisponda alla porta che si sta utilizzando.

puoi chiamare il metodo in qualsiasi punto del tuo programma con la seguente riga

 Print2LPT.Print(); 

Penso che questa sia la soluzione più breve ed efficiente al tuo problema.