Question

I am a Java programmer trying to transition to C# and I’m hoping there’s a way to do something in C# that I’m accustomed to in Java: overriding a method in the declaration of an abstract object like so:

//This is the way I do it in Java and want to do in C#
Keyword k = new Keyword("quit"){
    public abstract void do(String context){
        //TODO Do stuff
    }
};

This is for some text game stuff I’ve been doing for a while in Java. I’ve looked into abstract and virtual and anonymous classes but none of them do exactly this. Abstract and virtual want me to create a whole new subclass, but this would be time consuming and unfeasible on a large scale. Anonymous classes don’t (as far as I can tell) enable me to override methods, just fields and don’t provide any stabilization for me to rely on.

If there is a way to do this or something similar please explain. Thanks for your time.

Answer 1

That doesn’t work in C#. You’ll have to create a new class that inherits from Keyword.

public class MyKeyword : Keyword
{
    public MyKeyword(string s) : base(s)
    { }

    public override void do(string context)
    {
        // TODO: Do stuff.
    }
}

Anonymous Types in C# aren’t classes that you can provide any public methods for. They only have properties, and are intended to be a quick, intra-method way of pasing complex data from one line to the next.

To be honest, I didn’t know you could do what you show in Java. That is, if I’m understanding it as kind of an in-line class derivation.

Brian Rasmussen mentions using a delegate. That would look something like this:

public delegate void DoSomething(string context);
public class Keyword
{
    public DoSomething Do;

    private void CallsDo()
    {
        if (Do != null)  Do("some string");
    }
}

Then you can assign to it:

Keyword k = new Keyword();
k.Do = (ctx) => { /* Do something with ctx string */ };