using System; 
namespace ConsoleApplication7 
{ 
      class Program 
      { 
               static void Main(string[] args) 
               { 
                          people p = new people("Name1"); 
                          p.PropertyChanged += new EventHandler(p_PropertyChanged);
                          //注册事件处理函数 
                          p.Name = "Name2"; Console.ReadKey(); 
                          
               } 
               
               static void p_PropertyChanged(object sender, EventArgs e)
               //事件的处理函数 
               { 
                      Console.WriteLine("NamePropertyChanged:"+(sender as people).Name);                       
               } 
      } 
      
      class people 
      { 
          public event EventHandler PropertyChanged; 
          private string name=String .Empty; 
          public people(string name) 
          { 
              this.name = name; 
          } 
          public string Name 
          { 
             get { return name; } 
             set
             { name = value;               
               this.OnPropertyChanged(new EventArgs()); 
               //每次改变Name值调用方法;            
             } 
           } 
           
          private void OnPropertyChanged(EventArgs eventArgs) 
          { 
             if (this.PropertyChanged != null)
             //判断事件是否有处理函数 
             { 
                 this.PropertyChanged(this, eventArgs); 
             } 
          }
    } 
}