public delegate void Print(string str);static void delegatemethod(string str){Console.WriteLine(str);}public static void Main(){#region 委托//1.普通委托var print1 = new Print(delegatemethod);print1("这是普通方式创建的委托");//2.匿名委托Print print2 = delegate(string str) {Console.WriteLine(str);};print2("这是匿名方式创建的委托");//3.lambda委托Print print3 = (string str) => {Console.WriteLine(str);};}

//事件参数public class My_EventArgs : EventArgs{private string _args = string.Empty;public My_EventArgs(string args){_args = args;}public string Args{get { return _args; }}}//事件发行者public class SourceClass{public double Width { get; set; }public double Height { get; set; }My_EventArgs Evargs;public SourceClass(string args){Evargs = new My_EventArgs(args);}//定义委托public delegate void EventHandler(object sender, My_EventArgs args);#region 使用委托方式声明public EventHandler Clicked;public void ClickedAsync(){if (Clicked != null){Clicked(this, Evargs);}}#endregion#region 使用事件方式声明public event EventHandler Click;public void ClickAsync(){if (Click != null){Click(this, Evargs);}}#endregion}//事件订阅者public class Del{public delegate void Print(string str);static void delegatemethod(string str){Console.WriteLine(str);}public static void Main(){#region 委托//1.普通委托var print1 = new Print(delegatemethod);print1("这是普通方式创建的委托");//2.匿名委托Print print2 = delegate(string str) {Console.WriteLine(str);};print2("这是匿名方式创建的委托");//3.lambda委托Print print3 = (string str) => {Console.WriteLine(str);};print3("这是lambda方式创建的委托");#endregion#region 事件SourceClass source = new SourceClass("我的事件被触发");source.Width = 5.0;source.Height = 3.0;//一、委托方式允许source.Clicked(source, new My_EventArgs("我使用委托方式调用的Args"));调用source.Clicked = new SourceClass.EventHandler(source_RightClick);source.Clicked += new SourceClass.EventHandler(source_LeftClick);source.ClickedAsync();source.Clicked(source, new My_EventArgs("我使用委托方式调用的Args"));//二、很明显用户希望通过使用source.ClickedAsync();去调用函数，而非直接使用上行代码去调用，所以在这里需要使用Event关键字进行申明//注1.事件方式不允许source.Clicked(source, new My_EventArgs("我使用委托方式调用的Args"));直接调用//注2.事件不允许 source.Click = new SourceClass.EventHandler(source_LeftClick);直接赋值source.Click += new SourceClass.EventHandler(source_LeftClick);source.ClickAsync();//注销事件和注册事件source.Click -= new SourceClass.EventHandler(source_LeftClick);source.Click += new SourceClass.EventHandler(source_RightClick);source.ClickAsync();Console.ReadLine();#endregion}//事件处理方法1static void source_LeftClick(object sender, My_EventArgs args){SourceClass source = sender as SourceClass;Console.WriteLine("目标宽度:" + source.Width + "，目标高度:" + source.Height);Console.WriteLine("目标对象参数:"+args.Args);}//事件处理方法2static void source_RightClick(object sender, My_EventArgs args){SourceClass source = sender as SourceClass;Console.WriteLine("目标面积:" + source.Width *source.Height);}}