Accessing Device Drivers from C#

Example 7
CTL_CODE and DEVICE_TYPE_FROM_CTL_CODE

public static int CTL_CODE(int DeviceType, int Function, int Method, 
    int Access) {
   return 
     (((DeviceType) << 16)|((Access) << 14)|((Function) << 2)|(Method));
} 
    
public int DEVICE_TYPE_FROM_CTL_CODE(int ctrlCode)     { 
    return (int)(( ctrlCode & 0xffff0000) >> 16) ;
}