Defines the class of the dialog box.
The CLASS statement appears in the optional section before a DIALOG statement's main. If no class is given, the standard dialog class is used.
A 16-bit unsigned integer or a string, enclosed in double quotation marks ("), that identifies the class of the dialog box. If the window procedure for the class does not process a message sent to it, it must call the DefDlgProc function to ensure that all messages are handled properly for the dialog box. A private class can use DefDlgProc as the default window procedure. The class must be registered with the cbWndExtra member of the WNDCLASS structure set to DLGWINDOWEXTRA.
The CLASS statement should only be used with special cases, because it overrides the normal processing of a dialog box. The CLASS statement converts a dialog box to a window of the specified class; depending on the class, this could give undesirable results. Do not use the redefined control-class names with this statement.
The following example demonstrates the use of the CLASS statement: