1 .首先定义一个参数类 public partial class SayEventArgs : EventArgs ... { public String Username; public String Websiteurl;} 2 .定义一个委托 public delegate void SayEventHandler( object sender,SayEventArgs e); 3 .定义一个事件 public event SayEventHandler SayEvent; 4 .引发事件 public void OnSayEvent(SayEventArgs e) ... { if (SayEvent != null) ...{ SayEvent(this, e); }} 5 .传参函数 public void Loginsite(String Username, String Websiteurl) ... { SayEventArgs e = new SayEventArgs(); e.Username = Username; e.Websiteurl = Websiteurl; Label1.Text = e.Username + "<br>"; Label1.Text += "欢迎你来到<a href=" + e.Websiteurl + ">baozhenliang</a>"; OnSayEvent(e);} 6 .所要委托的函数 public void Saysomething( object sender, SayEventArgs e) ... { Label2.Text = e.Username+"请注意:<br>there are sth. <a href=" + e.Websiteurl + "> happening,ok?";} 7 .建立委托实例SayEvent += new SayEventHandler(Saysomething); Loginsite( " baozhenliang " , " u/admin/index.html " );看到了吗?定义事件也就这几步,要复杂点的话就把函数写得复杂点就行了。就这样。