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Updated: 12:31 PM CT Sep 01, 2007 Posted: 12:31 PM CT Sep 01, 2007 Delegate Syntax and Usage in C# Author: Steve Lautenschlager Reference Beginner Data Types Events C#  Overview How do I create a delegate in C#? Delegate Type Declaration in C# // simple delegate type declaration public delegate void MessageHandler(string message); // with various input parameters public delegate int CountDaysHandler(CountMethod method, DateTime startDate, DateTime endDate) Delegate Method Definition in C# // Defining the delegate public void HandleMessage(string message) { // do something with the message } public int CountDays(CountMethod method, DateTime startDate, DateTime endDate) { // return the number of days between the dates using the desired technique return -1; } // Define the delegate as an event public class MyClass { public event MessageHandler OnMessage; } Instantiate and Assign the Delegate // declare a new MessageHandler delegate private MessageHandler _MyMessageHandler = new MessageHandler(HandleMessage); private CountDaysHandler _MyCounter = new CountDaysHandler(CountDays); // register a delegate with an event MyClass.OnMessage += new MessageHandler(HandleMessage); // un-register MyClass.OnMessage -= new MesageHandler(HandleMessage); // View list of registered delgates Delegate[] delegateList = OnMessage.GetInvocationList(); foreach (Delegate d in delegateList) { // do something with the delegate }