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 win32 msgs: WM_PRINT

The WM_PRINT message is sent to a window to request that it draw itself in the specified device context, most commonly in a printer device context.

A window receives this message through its WindowProc function.

    LRESULT CALLBACK WindowProc(
      HWND hwnd,       // handle to window
      UINT uMsg,       // WM_PRINT
      WPARAM wParam,   // handle to DC (HDC)
      LPARAM lParam    // drawing options
    );

Parameters

• wParam
Handle to the device context to draw in.
• lParam
Specifies the drawing options. This parameter can be one or more of the following values. Value Meaning
• PRF_CHECKVISIBLE Draws the window only if it is visible.
• PRF_CHILDREN Draws all visible children windows.
• PRF_CLIENT Draws the client area of the window.
• PRF_ERASEBKGND Erases the background before drawing the window.
• PRF_NONCLIENT Draws the nonclient area of the window.
• PRF_OWNED Draws all owned windows.

Remarks

The DefWindowProc function processes this message based on which drawing option is specified: if PRF_CHECKVISIBLE is specified and the window is not visible, do nothing, if PRF_NONCLIENT is specified, draw the nonclient area in the specified device context, if PRF_ERASEBKGND is specified, send the window a WM_ERASEBKGND message, if PRF_CLIENT is specified, send the window a WM_PRINTCLIENT message, if PRF_CHILDREN is set, send each visible child window a WM_PRINT message, if PRF_OWNED is set, send each visible owned window a WM_PRINT message.

Requirements

• Windows NT/2000 or later: Requires Windows NT 4.0 or later.
• Windows 95/98/Me: Requires Windows 95 or later.
• Header: Declared in Winuser.h; include Windows.h.

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time