WM_DISPLAYCHANGE message

The WM_DISPLAYCHANGE message is sent to all windows when the display resolution has changed.

A window receives this message through its WindowProc function.

LRESULT CALLBACK WindowProc(
  HWND hwnd, 
  UINT  uMsg, 
  WPARAM wParam, 
  LPARAM lParam   
);

Parameters

wParam

The new image depth of the display, in bits per pixel.

lParam

The low-order word specifies the horizontal resolution of the screen.

The high-order word specifies the vertical resolution of the screen.

This message is only sent to top-level windows. For all other windows it is posted.

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Header	Winuser.h (include Windows.h)