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4/8/2010

This function removes a window class, freeing the memory required for the class.

Syntax 

BOOL UnregisterClass( 
  LPCTSTR 
lpClassName, 
  HINSTANCE 
hInstance
);

Parameters

lpClassName

Long pointer to an atom or null-terminated string. If lpClassNameis a string, it specifies the window class name. This class name must have been registered by a previous call to the RegisterClassfunction. System classes, such as dialog box controls, cannot be unregistered.

If this parameter is an atom, it must be a class atom created by a previous call to the RegisterClassfunction. The atom must be in the low-order word of lpClassName; the high-order word must be zero.

hInstance

Ignored.

Return Value

Nonzero indicates success. Zero indicates that the class could not be found or if a window still exists that was created with the class. To get extended error information, call GetLastError.

Remarks

Before calling this function, an application must destroy all windows created with the specified class.

All window classes that an application registers are unregistered when it terminates.

Requirements

Header winuser.h
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also