Your installation program can provide support for context menu operations, such as Open, Print, and Print To, by setting appropriate registry entries. The context menu appears when the user clicks mouse button 2 on a document associated with your application. Microsoft Installer Technology, makes adding these operations easy.
Enabling Print in the registry gives the shell instructions about what to execute when the user chooses Print from the context menu. Usually an application will display a dialog box that says " Printing page n of N on LPTX."
Enabling Print To in the registry specifies the default action for "drag print." Print To displays the same dialog box as Print when you drag it to a specific printer. The Print To option is not displayed on the context menu, so it does not bring up anything (that is, it cannot be chosen).
The following example shows how to set commands for the context menu for files having the .WRI filename extension.
HKEY_CLASSES_ROOT\.wri = wrifile
HKEY_CLASSES_ROOT\wrifile = Write Document
HKEY_CLASSES_ROOT\wrifile\DefaultIcon =
C:\Progra~1\Access~1\WORDPAD.EXE,2
HKEY_CLASSES_ROOT\wrifile\shell\open\command = WORDPAD.EXE %1
HKEY_CLASSES_ROOT\wrifile\shell\print\command =
C:\Progra~1\Access~1\WORDPAD.EXE /p "%1"
HKEY_CLASSES_ROOT\wrifile\shell\printto\command =
C:\Progra~1\Access~1\WORDPAD.EXE /pt "%1" "%2" "%3" "%4"
In the preceding commands, the %1 parameter is the filename, %2 is the printer name, %3 is the driver name, and %4 is the port name. In Windows 95, you can ignore the %3 and %4 parameters (the printer name is unique in Windows 95).