An application can examine public window class data by using the WinQueryClassInfo and WinQueryClassName functions. An application retrieves the name of the class for a given window by using the WinQueryClassName function. If the window is one of the preregistered public window classes, the name returned is in the form #nnnnn, where nnnnn is up to 5 digits, representing the value of the window class constant. Using this window class name, the application can call WinQueryClassInfo to retrieve the window class data. WinQueryClassInfo copies the class style, window procedure address, and window data size to a CLASSINFO data structure.