On Win32 platforms the full or long printer name is given by the pPrinterName member of the PRINTER_INFO_2 structure or by the DEVNAMES structure. The PRINTER_INFO_2 structure can be obtained from the EnumPrinters function. The DEVNAMES structure can be obtained by a call to either the PrintDlg or PrintDlgEx functions to fill a PRINTDLG(EX) structure. The DEVNAMES structure is managed by a global memory handle returned in the PRINTDLG(EX) structure.
The pPrinterName member of the PRINTER_INFO_2 structure and the name of the device (wDeviceOffset refers to the printer name) in the DEVNAMES structure are pointers to a string buffer. Because they are pointers to a string, they do not have a 32-character limitation and will contain the long printer name of the target printer. See the Platform SDK Documentation for a discussion of the PRINTDLG(EX) structure and the DEVNAMES structure.
Some applications may need to open a printer by name while printing to a printer device context. Such a circumstance occurs when the application is changing the settings of a DEVMODE buffer as described in the following Microsoft Knowledge Base article:
The GetPrinter function can fill out a single PRINTER_INFO_2 structure much like the EnumPrinters function can retrieve several such structures. Because proper changes to a DEVMODE also require a handle to a printer, such a handle is a convenient reference to the printer.
The long printer name can be used to obtain a handle to a printer through the OpenPrinter function, so the long name is also a convenient reference to the printer. It can be stored separately or as part of a DEVNAMES structure.
The printer name in a DEVNAMES buffer is stored in the extra space allocated beyond the DEVNAMES structure. To locate the printer name string in the DEVNAMES buffer, you can use the wDeviceOffset member to compute a pointer value that is based on the start of the DEVNAMES structure.
The following code fragment demonstrates the technique by creating a printer device context from a DEVNAMES and a DEVMODE structure:
HDC CreateDeviceContext( DEVMODE *pDevMode, DEVNAMES *pDevNames )
szDriver = (LPCTSTR)pDevNames+pDevNames->wDriverOffset;
szDevice = (LPCTSTR)pDevNames+pDevNames->wDeviceOffset;
szOutput = (LPCTSTR)pDevNames+pDevNames->wOutputOffset;
return CreateDC(szDriver, szDevice, szOutput, pDevMode);
For additional information regarding DEVMODE buffers, click the article number below to view the article in the Microsoft Knowledge Base:
ID d'article : 240082 - Dernière mise à jour : 3 mars 2009 - Révision : 1