ZPL(Zebra Programming Language) 是斑马公司(做条码打印机的公司)自己设计的语言, 由于斑马打印机是如此普遍, 以至于据我所见所知, 条码打印机全部都是斑马的, 所以控制条码打印机几乎就变成了对ZPL的使用.
总的逻辑分为以下两步:
(1)编写ZPL指令
(2)把ZPL作为C#的字符串, 由C#把它送至连接打印机的端口.
其中, 用C#把字符串送并口的写法是固定的, 这部分的代码如下:
public class Printer
{
[System.Runtime.InteropServices.StructLayout(System.Runtime.InteropServices.LayoutKind.Sequential)]
private struct OVERLAPPED
{
int Internal;
int InternalHigh;
int Offset;
int OffSetHigh;
int hEvent;
} [System.Runtime.InteropServices.DllImport("kernel32.dll")]
private static extern int CreateFile(
string lpFileName,
uint dwDesiredAccess,
int dwShareMode,
int lpSecurityAttributes,
int dwCreationDisposition,
int dwFlagsAndAttributes,
int hTemplateFile
); [System.Runtime.InteropServices.DllImport("kernel32.dll")]
private static extern bool WriteFile(
int hFile,
byte[] lpBuffer,
int nNumberOfBytesToWrite,
out int lpNumberOfBytesWritten,
out OVERLAPPED lpOverlapped
); [System.Runtime.InteropServices.DllImport("kernel32.dll")]
private static extern bool CloseHandle(
int hObject
); private int iHandle; public bool Open()
{
iHandle = CreateFile("LPT1:", (uint)FileAccess.ReadWrite, 0, 0, (int)FileMode.Open, 0, 0);
if (iHandle != -1)
{
return true;
}
else
{
return false;
}
} 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("端口未打开!");
}
} public bool Close()
{
return CloseHandle(iHandle);
} }
这个类封装了对并口的操作, 它的使用方法为:
var printer = new Printer();
if (!printer.Open())
{
GB.IO.SetError("未能连接打印机，请确认打印机是否安装正确并接通电源。");
return;
}
printer.Write(cmd);
if (!printer.Close())
{
GB.IO.SetError("未能关闭与打印机之间的连接，这可能意味着严重的错误，请重启电脑及打印机。");
return;
}
其中, cmd即是构造好的ZPL指令.
现在来看一段示意ZPL指令.
^XA ^MD30 ^LH60,10 ^FO20,10 ^ACN,18,10 ^BY1.4,3,50 ^BC,,Y,N ^FD01008D004Q-0^FS ^XZ
这是一段能够实际执行的指令串, 下面逐行解释.
第一句^XA和最后一句^XZ分别代表一个指令块的开始和结束, 是固定的东西.
^MD是设置色带颜色的深度, 取值范围从-30到30, 上面的示意指令将颜色调到了最深.
^LH是设置条码纸的边距的, 这个东西在实际操作上来回试几次即可.
^FO是设置条码左上角的位置的, 这个对程序员应该很容易理解. 0,0 代表完全不留边距.
^ACN是设置字体的. 因为在条码下方会显示该条码的内容, 所以这里要设一下字体. 这个字体跟条码无关.
^BY是设置条码样式的, 这是最重要的一个东西, 1.4是条码的缩放级别, 这个数值下打出的条码很小, 3是条码中粗细柱的比例, 50是条码高度.
^BC是打印code128的指令, 具体参数详见ZPL的说明书.
^FD设置要打印的内容, ^FS表示换行.
所以上述语句最终的效果就是打印出一个值为01008D004Q-0的条码, 高度为50.
以上可以看出, ZPL的指令方式很简单, 实际上, 如果打印要求不复杂的话, 基本上也就用得上上述的几个指令了,
其它的指令虽然很多, 但是基本上可以无视.
其实即使要打图形之类的东西, 也并不复杂, 例如GB可以打印出来一个边框, GC打印一个圆圈等. 其它的自定义图案需要先把图案上传至打印机,
指令部分只要选择已上传的图案, 选择方式跟上面的字体选择类似, 也很简单.
在实践中, 常常会需要一次横打两张, 其实可以把一排的两张想像成一张, 连续执行两个打印命令, 把第二个FO的横坐标设置得大一些就行了. 例如: ^XA ^FO20,10 ^FD001^FS ^FO60,10 ^FD002^FS ^XZ 第一对FO/FD命令打印左侧, 第二对FO/FD命令打印右侧.
具体的指令详细解释, 及要实现其它功能, 可下载 ZPL II Programming Guide, 这本书写得非常详细. (如链接不能下载, google书名即可)
----------2013/9/18 更新 将指令发送到打印机的代码， 上述做法仅限于打印机在本地，且接在并口1上面，如果打印机在远程， 或者打印机不是并口的， 可以通过驱动程序来发送指令。 这要求首先在操作系统中装好打印机驱动，调试无误以后， 记录下驱动中打印机的名称， 然后向此打印机发送指令， 与打印机驱动通信的类如下：
public class RemotePrinter
{
// 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.
SendBytesToPrinter(szPrinterName, pBytes, dwCount);
Marshal.FreeCoTaskMem(pBytes);
return true;
}
}
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在调用时， 只要调用RemotePrinter.SendStringToPrinter方法即可， 第一个参数是打印机的名称（驱动中显示的名称）， 第二个参数是命令。
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作者:夏狼哉 博客:http://www.cnblogs.com/Moosdau
如需引用,敬请保留作者信息,谢谢