Author Topic: Undocumented flag for "GetDCEx"  (Read 2424 times)

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Offline Theo Gottwald

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Undocumented flag for "GetDCEx"
« on: October 06, 2011, 03:56:33 PM »
GetDCEx can be used to retrieve the device context for a window during processing of %WM_NCPAINT.
The documentation states that this is achieved by using

Code: [Select]
GetDCEx(hwnd, hrgn, %DCX_WINDOW | %DCX_INTERSECTRGN)

However, this call never works, because there is an undocumented flag to include which is not mentioned anywhere.

And this is how it works:

Code: [Select]
GetDCEx(hwnd, hrgn, DCX_WINDOW | DCX_INTERSECTRGN | 0x10000)
Source: Catch22.net