test.cs

using System;

namespace test2
{
	public delegate void CallSuccess();
	public delegate void CallError(String e);

	public class Service
	{
		public void success(CallSuccess ok, CallError error) {
			ok();
		}

		public void error(CallSuccess ok, CallError error) {
			error("Error message");
		}

	}

	class MainClass
	{
		public static void Main (string[] args)
		{
			new Service ().success (() => { Console.WriteLine("ok");}, (e) => { Console.WriteLine("error : " + e); });
			new Service ().error (() => { Console.WriteLine("ok");}, (e) => { Console.WriteLine("error : " + e); });
		}
	}
}