[C#] Delegate & Event 예제 코드

Delegate & Event 예제

간단한 Delegate & Event 예제 입니다.

아래에서 주의 할 점은 public event 를 부를 수 있는 것은 그 event 가 속해있는 class의 method 뿐이라는 것입니다.

Anonymous Method 의 사용법도 눈여겨보시기 바랍니다.

Anonymous Method 를 사용할 때, close brace " } " 다음에 세미콜론 " ; " 을 붙여야합니다.

using System;

namespace DelegateSample
{
    class Program
    {
        static void Main(string[] args)
        {
            Human Tom = new Human();

            Tom.ActionDelegate += new Action(Tom.Speak);
            Tom.ActionDelegate += Tom.Shout;

            // Anonymous Method
            Tom.ActionDelegate += delegate(string words) 
            { 
                Console.WriteLine("Anonymous:" + words); 
            };

            Tom.ActionDelegate("Direct Called Delegate");
            Tom.RaiseActionDelegate("Delegate Raised by Method");

            Tom.ActionEvent += new Action(Tom.Speak);
            Tom.ActionEvent += Tom.Shout;

            // Anonymous Method
            Tom.ActionEvent += delegate(string words) 
            { 
                Console.WriteLine("Anonymous:" + words); 
            };

            // A public event can only be raised 
            // by methods within the class that defines it.
            // Tom.ActionEvent("Direct Called Event"); // Compile Error.

            Tom.RaiseActionEvent("Event Raised by Method");
        }

        delegate void Action(string words);

        class Human
        {
            public void Speak(string words)
            {
                Console.WriteLine("Speak:" + words);
            }

            public void Shout(string words)
            {
                Console.WriteLine("Shout:" + words);
            }

            public void RaiseActionDelegate(string words)
            {
                if (this.ActionDelegate != null)
                {
                    this.ActionDelegate(words);
                }
            }

            public void RaiseActionEvent(string words)
            {
                if (this.ActionEvent != null)
                {
                    this.ActionEvent(words);
                }
            }

            public Action ActionDelegate;
            public event Action ActionEvent;
        }
    }
}