UnregisterClass

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

At a Glance

Header file: Winuser.h
Windows CE versions: 1.0 and later

Syntax

BOOL UnregisterClass( LPCTSTR lpClassName, HINSTANCE hInstance );

Parameters

lpClassName

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

If this parameter is an integer atom, it must be a global atom created by a previous call to the RegisterClass function. The atom, a 16-bit value less than 0xC000, must be in the low-order word of lpClassName; the high-order word must be zero.

hInstance

Ignored.

Return Values

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.

See Also

RegisterClass