Lambda problem

Good morning everyone. I'm having a problem with this code that I'm trying to understand. I get a red wiggly line under the word "proxy.BeginAdd(" , this looks really wierd in that the closing parentheses is missing. It looks like a typo but since this is lambda and i don't know squat about lambda maybe this is legal? Can any of you guys guess at how this is supposed to be written if it is a typo? Or can you tell me what was the meant writing? Just placing a closing parenthesese around => didn't fix it. Also I don't know what "ar" is or where it's coming from either. Can someone please take a look at this and give me a hand?

Code:

---

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

using MathClient.ServiceReference1;
using System.Threading;

namespace MathClient
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("***** The Async Math Client *****\n");

            using (BasicMathClient proxy = new BasicMathClient())
            {
                proxy.Open();

                //add numbers in an async manner, using a lambda expression.
                IAsyncResult result = proxy.BeginAdd(2, 3,      //red squiggly line under proxy.BeginAdd(
                                        ar =>
                        {
                            Console.WriteLine("2 + 5 = {0}, proxy.EndAdd(ar));
                        }
                        while (!result.IsCompleted)
                        {
                            Thread.Sleep(200);
                            Console.WriteLine("Client working...");
                        }
                Console.ReadLine();
            }
        }
    }
}

---

The BeginAdd function takes 4 parameters. See the following:

Code:

---

IAsyncResult result = proxy.BeginAdd(2, 3, MyCallback, proxy);

---

If you didn't have a callback, put null. For additional help, with the callback, see http://med-adel.blogspot.com/2010/10...-wcf-part.html.

If this solution resolves your problem, please rate this post, and mark the thread resolved!

Regards,
Quinn

Hi there. Thanks a lot. It goes like this now and everything works.

Code:

---

static void Main(string[] args)
        {
            Console.WriteLine("***** The Async Math Client *****\n");

            using (BasicMathClient proxy = new BasicMathClient())
            {
                proxy.Open();

                //add numbers in an async manner, using a lambda expression.
                IAsyncResult result = proxy.BeginAdd(2, 3,
                      ar =>
                        {
                            Console.WriteLine("2 + 5 = {0}", proxy.EndAdd(ar));
                        },null);
                        while (!result.IsCompleted)
                        {
                            Thread.Sleep(200);
                            Console.WriteLine("Client working...");
                        }
                Console.ReadLine();
            }
        }

---

Glad I could help. :)