C # directly operate the parallel port

C # Only the class for direct serial port operation is provided. If you operate the parallel port directly, you need to call the API function:

Using system. runtime. interopservices;

String senddata = "^ XA ^ fo50, 80 ^ ADN, 36,20 ^ fdtrw eol2 ^ FS ^ xz"; // zebra printer Command Format
[Dllimport ("kernel32.dll")]
Private Static extern int createfile (
String lpfilename, // the serial port to be opened/parallel port name
Int dwdesiredaccess, // specifies the access method of the port, which is generally set to readable and writable.
Int dwsharemode, // The Sharing Mode of the specified port. The port cannot be shared, so it is set to 0.
Int lpsecurityattributes, // set the Security Attribute of the port. This parameter is not supported in Win9x and should be set to null.
Int dwcreationdisposition, // for serial communication, the creation method can only be open_existing
Int dwflagsandattributes, // specifies the serial port attribute and flag
Int htemplatefile); // for serial communication, the value must be set to null.
[Dllimport ("kernel32.dll")]
Public static extern void writefile (INT comhandle, string senddata, int strlen, ref int Alen, int zero );
[Dllimport ("kernel32.dll")]
Public static extern void closehandle (INT handle );
Int handle = createfile ("LPT1", 0x40000000, 0, 0, 3/** // * open_existing */, 0, 0 );
If (handle! = 0 ){
Writefile (handle, senddata, strlen, ref Alen, 0 );
Closehandle (handle); // note that the printer executes the command only after the parallel port is closed.