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2.1.25.36 GetWindowLong

Description

This function also retrieves the 32-bit (long) value at the specified offset into the extra window memory.

DWORD GetWindowLong( HWND hWnd, int nIndex )

hWnd: [input] Handle to the window and, indirectly, the class to which the window belongs.
nIndex: [input] Specifies the zero-based offset to the value to be retrieved.; Valid values are in the range zero through the number of bytes of extra window memory, minus four;; for example, if you specified 12 or more bytes of extra memory, a value of 8 would be an index to the third 32-bit integer. To retrieve any other value, specify one of the following values.

If the function succeeds, the return value is the requested 32-bit value.

If the function fails, the return value is zero.

origin.h