GetClassWord

The GetClassWord function retrieves the 16-bit (word) value at the specified offset into the extra class memory for the window class to which the specified window belongs.

Other than GCW_ATOM and GCW_HICONSM, the GCW_ values support by 16-bit Windows are obsolete. You must use the GetClassLong function to retrieve the class values of a window.

WORD GetClassWord(
  HWND hWnd,  // handle of window
  int nIndex  // offset of value to retrieve
);
 

Parameters

hWnd

Handle to the window and, indirectly, the class to which the window belongs.

nIndex

Specifies the zero-based byte offset of the value to be retrieved. Valid values are in the range zero through the number of bytes of class memory, minus two; for example, if you specified 10 or more bytes of extra class memory, a value of eight would be an index to the fifth 16-bit integer. There is an additional valid value:

Value	Action
GCW_ATOM	Retrieves an ATOM value that uniquely identifies the window class. This is the same atom that the RegisterClass function returns.
GCW_HICONSM	Retrieves the handle of the small icon associated with the window.

Return Values

If the function succeeds, the return value is the requested 16-bit value.

If the function fails, the return value is otherwise, it is zero. To get extended error information, call GetLastError.

Remarks

Reserve extra class memory by specifying a nonzero value in the cbClsExtra member of the WNDCLASS structure used with the RegisterClass function.

See Also

Window Classes Overview, Window Class Functions, GetClassLong, RegisterClass, SetClassWord, WNDCLASS