Creating a CallBack with anonymous delegates

With a callback, you tell one method another method to call when processing is complete. It's cool.

Here's an example use: let's say you need to call Save() and when save is complete you want to call Close(). That's easy unless Save() is asynchronous. In that case, pass Close() as a callback delegate to the Save() method [something like: Save(CloseDelegate callback)]. When the save function is complete, it can call Close() for you. Easy enough.

Here's a simple console application to show you how to do it. Just create a console project and paste this into your Program.cs file. I wrote this in Visual Studio 2008. Here you go:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplicationCallBack
{
    class Program
    {
        static void Main(string[] args)
        {
            RemoteClass _RemoteClass;
            _RemoteClass = new RemoteClass();
            _RemoteClass.Click(new ParentClass());
        }
    }

    class ChildClass
    {
        public string Text
        {
            get;
            set;
        }
        public ChildClass(string text)
        {
            this.Text = text;
        }
    }

    class ParentClass
    {
        List<ChildClass> m_List = new List<ChildClass>();
        public ParentClass()
        {
            m_List.Add(new ChildClass("Wes"));
            m_List.Add(new ChildClass("Eric"));
            m_List.Add(new ChildClass("Jerry"));
        }
        public delegate void MyDelegateFound(ChildClass child);
        public delegate void MyDelegateNotFound(string name);
        public void GetchildClass(string name, 
            MyDelegateNotFound myDelegate, 
            MyDelegateFound myDelegateFound)
        {
            foreach (ChildClass _Item in m_List)
            {
                if (_Item.Text == name)
                {
                    myDelegateFound.Invoke(_Item);
                    return;
                }
            }
            myDelegate.Invoke(name);
        }
    }

    class RemoteClass
    {
        public void Click(ParentClass centralClass)
        {
            ParentClass.MyDelegateFound _MyDelegateFound;
            _MyDelegateFound = 
                new ParentClass.MyDelegateFound(delegate(ChildClass child)
            {
                Console.WriteLine("Found: " + child.Text);
            });

            ParentClass.MyDelegateNotFound _MyDelegateNotFound;
            _MyDelegateNotFound = 
                new ParentClass.MyDelegateNotFound(delegate(string name)
            {
                Console.WriteLine("Not Found: " + name);
            });

            centralClass.GetchildClass("Jerry", 
                _MyDelegateNotFound, _MyDelegateFound);
            centralClass.GetchildClass("JerryFAIL", 
                _MyDelegateNotFound, _MyDelegateFound);
        }
    }
}