This method shuts down a control when it is removed from the form.
HRESULT Close( void );
NOERROR indicates success. If an error occurs, the appropriate HRESULT value is returned.
A form invokes this method when it wishes to close a control. The control frees all resources and releases all external reference counts. You must call this method for any initialized form, even if you have not called IASControl::Start on the form
If a message sink exists, this method invokes IASClassMsgSink::HandleClose.
IASControl::Init, IASClassMsgSink::HandleClose