How to disable Alt key,control key,windows key,Esc key and shift key in windows application using c#.net?

hi i worked the above first link like "Disable Special Keys in Win App C#[^]". i got one error for running time. The error is .

CallbackOnCollectedDelegate was detected
Message: A callback was made on a garbage collected delegate of type 'AppsNet!AppsNet.frmMain+LowLevelKeyboardProc::Invoke'. This may cause application crashes, corruption and data loss. When passing delegates to unmanaged code, they must be kept alive by the managed application until it is guaranteed that they will never be called.