kald af dll i c#

Hej. Jeg vil gerne kalde en dll der ser sådan ud:

Metode:
CreateKey( AHandle : THandle; Room, FirstName, LastName : PChar; CheckInDate, CheckOutDate :TDateTime; KeyPuncher, NoOfKeys, KeyType : Integer; Const HotelNo : Integer = -1 ; Const SimpleMode : Boolean = False ) : Boolean

Er dette rigtigt?

[DllImport("DllKey.dll", SetLastError=true,
        CharSet=CharSet.Unicode, ExactSpelling=true,
        CallingConvention=CallingConvention.StdCall)]
        public static extern bool CreateKey(int handle, ref char room, ref char firstename, ref char lastname, DateTime start,  DateTime end, int keypuncher, int noofkeys , int keytype, int hotelNumber, bool simpleMode);