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Managing Printers

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The Shell API provides functions that you can use to manage networked printers. If a file has the print verb associated with it, you can use the ShellExecuteEx command to print it.

Printer Management

You can manage printers on a system with the SHInvokePrinterCommand function. This function allows you to:

  • Install printers.
  • Open printers.
  • Get printer properties.
  • Create printer links.
  • Print a test page.

Printing Files with ShellExecuteEx

If a file type has a print command associated with it, you can print the file by calling ShellExecuteEx with print as the verb. This command is often the same as that used for the open verb, with the addition of a flag to tell the application to print the file. For instance, .txt files can be printed by Microsoft WordPad. The open verb for a .txt file would thus correspond to something like the following command:

"C:\Program Files\Windows NT\Accessories\Wordpad.exe" /p "%1"

When you use ShellExecuteEx to print a .txt file, WordPad opens the file, prints it, and then closes, returning control to the application. The following sample function takes a fully qualified path, and uses ShellExecuteEx to print it, using the print command associated with its file name extension.

#include <shlobj.h>

HINSTANCE PrintFile(LPCTSTR pszFileName)
{
    SHELLEXECUTEINFO ShExecInfo;
    HINSTANCE hInst;

    // Fill the SHELLEXECUTEINFO array.

    ShExecInfo.cbSize = sizeof(SHELLEXECUTEINFO);
    ShExecInfo.fMask = NULL;
    ShExecInfo.hwnd = NULL;
    ShExecInfo.lpVerb = "print";
    ShExecInfo.lpFile = pszFileName;  // a fully qualified path
    ShExecInfo.lpParameters = NULL;
    ShExecInfo.lpDirectory = NULL;    
    ShExecInfo.nShow = SW_MAXIMIZE;
    ShExecInfo.hInstApp = NULL;

    hInst = ShellExecuteEx(&ShExecInfo);
    
    return hInst;
}