c# deriving from int32

Question

i have several classes with members called \'Id\'. Originally i wanted to store these as ints, but i would like some layer of protection, to make sure i don\'t accidentally

Answer 1

You can't derive from Int32, but you can specify implicit conversions, which might give you the behaviour you need:

public struct RoomId
{
    private int _Value;

    public static implicit operator RoomId(int value)
    {
        return new RoomId { _Value = value };
    }

    public static implicit operator int(RoomId value)
    {
        return value._Value;
    }
}

// ...

RoomId id = 42;

Console.WriteLine(id == 41);    // False
Console.WriteLine(id == 42);    // True
Console.WriteLine(id < 42);     // False
Console.WriteLine(id > 41);     // True
Console.WriteLine(id * 2);      // 84