Registers a window class
#include <WinAPISysWin.au3>
_WinAPI_RegisterClass ( $tWNDCLASS )
| $tWNDCLASS | $tagWNDCLASS structure. |
| Success: | The value is a class atom that uniquely identifies the class being registered. |
| Failure: | 0, call _WinAPI_GetLastError() to get extended error information. |
Search RegisterClass in MSDN Library.