Mixed-type collections?

[Nochte]

It's been a SUPER long time since I've worked with C#, so I'm a bit fuzzy on this one.
Here's what I've got:

I have two classes; Player, and AIPlayer. AIPlayer is derived from Player. I want to use a container that will hold both types, and be able to call methods from each object as its own class. I've attempted ArrayList, using similar to the following code:

System.Collections.ArrayList players = new System.Collections.ArrayList();
Player one = new Player();
AIPlayer two = new AIPlayer();
players.Add(one);
players.Add(two);

players[0].Move;
players[1].Move;
...etc

players[0] returns an object, not a player or AIPlayer.
Ideas?

[Malaperth]

If you use an arraylist, the arraylist has no types, it can only return an object. You will have to test for type, and then cast it accordingly. Or, you can use a Generic List which you can type (if you are using .Net 2.0), and make it of the base type:

List<Player> list = new List<Player> ();

[Nochte]

So I can add any object to the list, as long as it's derived from player?

[Jeff]

Arraylists are object lists, whatever is in it, is assumed to be an object, thus when you get something out of it, you need to cast it as its type

System.Collections.ArrayList players = new System.Collections.ArrayList();
Player one = new Player();
AIPlayer two = new AIPlayer();
players.Add(one);
players.Add(two);

((Player)players[0]).Move;
((Player)players[1]).Move;
...etc

If you end up casting it as the wrong type, you will get a Invalid cast type exception and a crash.

Using a generic list, can give you a list that doesnt need casting. For example

System.Collections.Generics.List<Player> players = new System.Collections.Generics.List<Player>();
Player one = new Player();
AIPlayer two = new AIPlayer();
players.Add(one);
players.Add(two);

players[0].Move;//this will work
players[1].Move;//this will work

//If you needed to see if the specific player was a AIPlayer you could do this
if( players[0] is AIPlayer )
    ((AIPlayer)players[0]).DoThis();

Hope this helps

[Nochte]

It helps a lot. I've got it sorta working. When a property (move) is called, regardless of if it's Player or AIPlayer, the Player's move is used. How would I specify that the AIPlayer's move needs to be used when the type is AIPlayer?

Let me know if you need to see my declarations for everything, I'll attach on the next post. Thanks

[Jeff]

Originally Posted by Nochte

It helps a lot. I've got it sorta working. When a property (move) is called, regardless of if it's Player or AIPlayer, the Player's move is used. How would I specify that the AIPlayer's move needs to be used when the type is AIPlayer?

Let me know if you need to see my declarations for everything, I'll attach on the next post. Thanks

Is Move a virtual Function? if so, when you override it in the AIPlayer class, reguardless of it being Player or AIPlayer, it should call its top overriden function.

[Nochte]

It is not. Should I create a completely virtual base class Player, then derive AIPlayer and HumanPlayer (currently, Player is a human player) from it?

[Jeff]

Originally Posted by Nochte

It is not. Should I create a completely virtual base class Player, then derive AIPlayer and HumanPlayer (currently, Player is a human player) from it?

Doesnt matter how u do it, thats all preference but when you inherit methods you want ot be different the base class has to be virtual and the class inhereted to needs to override those methods to perform them differently.

Examples

public class BaseClass
{
    public BaseClass(){}

    public virtual void Foo() {}
}

public class InheretedClass : BaseClass
{
    public InheretedClass() : base() {}

    public override void Foo() {}
}

In this instance, if i cast InheredtedClass as a BaseClass, and call Foo it will call it at its InheretedClass level.

[Nochte]

Perfect. Exactly what I need. Thanks. I'll get back to ya later when I'm done.

Update:
Worked like a champ. Thanks for the help, Jeff and Mal