C#票据打印类

using System;

using System.Collections.Generic;

using System.Text;

using System.IO;

using System.Windows.Forms;

using Microsoft.Win32.SafeHandles;
using System.Runtime.InteropServices;

using System.ComponentModel;



namespace Comm

...{

    publicclass TicketPrinter

    ...{

        publicconstshort FILE_ATTRIBUTE_NORMAL =0x80;

        publicconstshort INVALID_HANDLE_VALUE =-1;

        publicconstuint GENERIC_READ =0x80000000;

        publicconstuint GENERIC_WRITE =0x40000000;

        publicconstuint CREATE_NEW =1;

        publicconstuint CREATE_ALWAYS =2;

        publicconstuint OPEN_EXISTING =3;



        [DllImport("inpout32.dll", EntryPoint ="Out32")]

        privatestaticexternvoid Output(int adress, int value);



        [DllImport("inpout32.dll", EntryPoint ="Inp32")]

        privatestaticexternint Input(int adress);  





        private SafeFileHandle TicketPrinterHandle =null;

        [DllImport("kernel32.dll", SetLastError =true)]

        staticextern SafeFileHandle CreateFile(

            string lpFileName, 

            uint dwDesiredAccess,

            uint dwShareMode, 

            IntPtr lpSecurityAttributes, 

            uint dwCreationDisposition,

            uint dwFlagsAndAttributes, 

            IntPtr hTemplateFile);



        [DllImport("kernel32.dll", SetLastError =true)]

        privatestaticexternbool WriteFile(

         SafeFileHandle hFile,            // handle to file

         char[] lpBuffer,                       // data buffer

         int nNumberOfBytesToWrite,   // number of bytes to write

         outint lpNumberOfBytesWritten,  // number of bytes written

         IntPtr lpOverlapped          // overlapped buffer

         );



        [DllImport("kernel32.dll", SetLastError =true)]

        privatestaticexternbool CloseHandle(

         SafeFileHandle hObject   // handle to object

         );





        privatestring _PPort ="";

        publicstring Status ="正在检测...";



        public TicketPrinter()

        ...{



        }



        publicvoid Create( string LPTName )

        ...{

            _PPort ="";

            TicketPrinterHandle = CreateFile(

                 LPTName, GENERIC_WRITE, 0, IntPtr.Zero,

                  OPEN_EXISTING, 0, IntPtr.Zero);

            if (TicketPrinterHandle.IsInvalid)

            ...{

                MessageBox.Show("票据打印机口不能打开！");

                return;

            }

            _PPort = LPTName;

        }



        publicvoid Close()

        ...{

            if (TicketPrinterHandle ==null)

                return;

            if (TicketPrinterHandle.IsInvalid)

                return;

            CloseHandle(TicketPrinterHandle);

        }



        publicvoid Print(string str)

        ...{

            Print(str, "left");

        }



        publicvoid Print(string str, string align)

        ...{

            if (TicketPrinterHandle ==null)

                return;

            if (TicketPrinterHandle.IsInvalid)

                return;

            int PadCount =30;

            PadCount -= StrLen( str );

            if (align =="center")

                str = str.PadLeft(PadCount /2+ str.Length, '');

            elseif (align =="right")

                str = str.PadLeft(PadCount, '');



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

            //  7     6      5      4       3       2       1       0

            // Busy  nAck Paper-Out Select nError   x       x       x

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

            //check Parallel port Status registers 

            int RetryCount =10;

            Retry:

            int sta =0;

            if (_PPort =="LPT1")

                sta = Input(0x379);

            elseif (_PPort =="LPT2")

                sta = Input(0x279);



            if( sta ==0x7F )

            ...{

                Status ="未连接";

                return;

            }

            if ((sta &0x10) ==0)

            ...{

                Status ="未上电";

                return;

            }

            if ((sta &0x80) ==0)      //Busy

            ...{

                Status ="打印机忙";

                RetryCount--;

                if (RetryCount <=0)

                    return;

                goto Retry;

            }

            if ((sta &0x20) !=0)      //Paper-Out

            ...{

                Status ="打印机缺纸";

                return;

            }