An event handler is a callback routine that operates asynchronously and handles inputs received into a program (events).

using System;

namespace IntroEventHandler { class myEventArgs : EventArgs { public string Message { get; set; } public string Name { get; set; }

}

}

using System;

namespace IntroEventHandler { class CustomeClass { public event EventHandler OnComplete;

    public void DoSomeWork()
    {
        myEventArgs args = new myEventArgs();
        args.Message = "This is work done!";
        OnComplete(this, args);
    }
}

}

using System;

namespace IntroEventHandler { class Program { static void Main(string[] args) { CustomeClass aCustomeClass = new CustomeClass(); aCustomeClass.OnComplete += new EventHandler(PrintMessage); aCustomeClass.DoSomeWork(); }

    private static void PrintMessage(object sender, EventArgs e)

    {
        Console.WriteLine("Event fired!");
        Console.ReadKey();

    }
}

}