Question

Is there a way to control the type conversion in C#? So for example, if I have two types with essentially the same details, but one is used for the internal working of my application and the other is a DTO used for communicating with non-.Net applications:

public sealed class Player
{
  public Player(string name, long score)
  {
    Name = name;
    Score = score;
    ID = Guid.NewGuid();
  }

  public string Name { get; private set; }

  public Guid ID { get; private set; }

  public long Score { get; private set; }
}

public sealed class PlayerDTO
{
  public PlayerDTO(string name, long score, string id)
  {
    Name = name;
    Score = score;
    ID = id;
  }

  public string Name { get; private set; }

  // the client is not .Net and doesn't have Guid
  public string ID { get; private set; }  

  public long Score { get; private set; }
}

Right now, I need to create a new instance of PlayerDTO from my Player instance every time and I’m looking for a better, cleaner way of doing this.
One idea I had was to add an AsPlayerDTO() method to the player class, but would be nice if I can control the type conversion process so I can do this instead:

var playerDto = player as PlayerDTO; 

Anyone know if this is possible and how I might be able to do it?

Thanks,

Answer 1

You can implement either implicit or explicit type conversion: http://msdn.microsoft.com/en-us/library/ms173105.aspx.

Alternately, if you want to avoid making each class having to know about the other, you can use either custom mapping or an existing mapping library like AutoMapper.