C#通過LPT1連接埠控制印表機

//C#控制印表機(直接發送印表機命令到印表機)

//一個印表機控制類,很有用的,其中使用了windows api控制lpt連接埠,對條碼印表機的控制方法如下:將印表機的命令寫到一個檔案裡，再使用之。

//代碼：

using System;

using System.Collections.Generic;

using System.Text;

using System.Runtime.InteropServices;

 

namespace LPTControls

{

    public class LPTControls

    {

        [StructLayout(LayoutKind.Sequential)]

        private struct OVERLAPPED

        {

            int Internal;

            int InternalHigh;

            int Offset;

            int OffSetHigh;

            int hEvent;

        }

        [DllImport("kernel32.dll")]

        private static extern int CreateFile(string lpFileName, uint dwDesiredAccess, int dwShareMode, int lpSecurityAttributes, int dwCreationDisposition, int dwFlagsAndAttributes, int hTemplateFile);

 

        [DllImport("kernel32.dll")]

        private static extern bool WriteFile(int hFile, byte[] lpBuffer, int nNumberOfBytesToWriter, out int lpNumberOfBytesWriten, out OVERLAPPED lpOverLapped);

 

        [DllImport("kernel32.dll")]

        private static extern bool CloseHandle(int hObject);

 

        private int iHandle;

 

        //開啟LPT 連接埠

        public bool Open()

        {

            iHandle = CreateFile("lpt1", 0x40000000, 0, 0, 3, 0, 0);

            if (iHandle != -1)

            {

                return true;

            }

            else

            {

                return false;

            }

        }

        //列印函數，參數為印表機的命令或者其他文本！

        public bool Write(string MyString)

        {

            if (iHandle != 1)

            {

                int i;

                OVERLAPPED x;

                byte[] mybyte = System.Text.Encoding.Default.GetBytes(MyString);

                return WriteFile(iHandle, mybyte, mybyte.Length, out i, out x);

            }

            else

            {

                throw new Exception("連接埠未開啟~！");

            }

        }

        //關閉列印連接埠

        public bool Close()

        {

            return CloseHandle(iHandle);

        }

    }

}

 

//***************************************************************

//使用方法

private void button1_Click(object sender, EventArgs e)

{

    LPTControls.LPTControls lpt = new LPTControls.LPTControls();

    string mycommanglines = System.IO.File.ReadAllText("print.txt");//print.txt裡寫了條碼機的命令

    lpt.Open();

    lpt.Write(mycommanglines);

    lpt.Close();

 

}