Deletes the specified device context
#include <WinAPIGdiDC.au3>
_WinAPI_DeleteDC ( $hDC )
| $hDC | Identifies the device context to be deleted | 
| Success: | True | 
| Failure: | False | 
An application must not delete a DC whose handle was obtained by calling the _WinAPI_GetDC() function.
Instead, it must call the _WinAPI_ReleaseDC() function to free the DC.
_WinAPI_CreateCompatibleDC, _WinAPI_GetDC, _WinAPI_ReleaseDC
Search DeleteDC in MSDN Library.