Zitat:
Return Values
If the function succeeds, the return value is an atom that uniquely identifies the class being registered.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
Delphi-Quellcode:
var
wc : TWndClassEx = (
cbSize : SizeOf(TWndClassEx);
Style : CS_HREDRAW or CS_VREDRAW;
lpfnWndProc : @WndProc;
cbClsExtra : 0;
cbWndExtra : 0;
hbrBackground : COLOR_APPWORKSPACE;
lpszMenuName : nil;
lpszClassName : ClassName;
hIconSm : 0;
);