// 定义代理
 public delegate void LogInOutClickHandler(object sender,LogInOutEventArgs e);
 public class LogInOutControl : System.Web.UI.UserControl
 {
  protected System.Web.UI.WebControls.Button ButtonLogIn;
  protected System.Web.UI.WebControls.TextBox TextBoxUserName;
  protected System.Web.UI.WebControls.TextBox TextBoxPassword;
  protected System.Web.UI.WebControls.Button ButtonLogOut;
  protected System.Web.UI.WebControls.Label LabelUser;
  protected System.Web.UI.WebControls.Label LabelPassword;
  public event LogInOutClickHandler LogInOutClick;
  private Language language;
  //方法
  public void ChangeLanguage(Language language)
  {
   this.Lg = language;
  }
  //属性
  public Language Lg
  {
   set
   {
    if(value!=this.language)
    {
     if(value==Language.English)
     {
      this.LabelUser.Text = "User:";
      this.LabelPassword.Text ="Password:";
      this.ButtonLogIn.Text = "LogIn";
      this.ButtonLogOut.Text = "LogOut";
     }
     else
     {
      this.LabelUser.Text = "用户：";
      this.LabelPassword.Text ="密码：";
      this.ButtonLogIn.Text = "登录";
      this.ButtonLogOut.Text = "注销";
     }
    }
   }
  }
  private void Page_Load(object sender, System.EventArgs e)
  {
   if(this.LabelUser.Text=="User:")
     this.language = Language.English;
    else
     this.language = Language.Chinese;
  }
  private void OnLogInOutClick(object sender,LogInOutEventArgs e)
  {
   if(LogInOutClick!=null)
    LogInOutClick(this,e);
  }
  #region Web 窗体设计器生成的代码
  override protected void OnInit(EventArgs e)
  {
   InitializeComponent();
   base.OnInit(e);
  }
private void InitializeComponent()
  {
   this.ButtonLogIn.Click += new System.EventHandler(this.ButtonLogIn_Click);
   this.ButtonLogOut.Click += new System.EventHandler(this.ButtonLogOut_Click);
   this.Load += new System.EventHandler(this.Page_Load);
  }
  #endregion
  private void ButtonLogIn_Click(object sender, System.EventArgs e)
  {
   OnLogInOutClick(this,new LogInOutEventArgs(LogInClickType.LongIn,CustomValidate(this.TextBoxUserName.Text,this.TextBoxPassword.Text)));
  }
  private void ButtonLogOut_Click(object sender, System.EventArgs e)
  {
   //注销代码省略
   OnLogInOutClick(this,new LogInOutEventArgs(LogInClickType.LongOut,true));
  }
  //验证函数
  private bool CustomValidate(string userName,string password)
  {
   //验证代码省略，假设通过
   return true;
  }
 }
}

namespace ZZ
{
 public class Default : System.Web.UI.Page
 {
  protected System.Web.UI.WebControls.Label LabelMsg;
  protected System.Web.UI.WebControls.DropDownList DropDownList1;
  protected LogInOutControl LogInOutControl1;
  private void Page_Load(object sender, System.EventArgs e)
  {
   //注册用户控件事件
   this.LogInOutControl1.LogInOutClick += new LogInOutClickHandler(LogInOutControl1_LogInOutClick);
  }
  #region Web 窗体设计器生成的代码
  override protected void OnInit(EventArgs e)
  {
   InitializeComponent();
   base.OnInit(e);
  }
  private void InitializeComponent()
  {   
   this.DropDownList1.SelectedIndexChanged += new System.EventHandler(this.DropDownList1_SelectedIndexChanged);
   this.Load += new System.EventHandler(this.Page_Load);
  }
  #endregion
  private void LogInOutControl1_LogInOutClick(object sender, LogInOutEventArgs e)
  {
   switch(e.Type)
   {
    case LogInClickType.LongIn:
     this.LabelMsg.Text = "你点击了登录按钮，操作结果："+e.Result.ToString();
     break;
    case LogInClickType.LongOut:
     this.LabelMsg.Text = "你点击了注销按钮，操作结果："+e.Result.ToString();
     break;
   }
  }
private void DropDownList1_SelectedIndexChanged(object sender, System.EventArgs e)
  {
   this.LogInOutControl1.Lg = (Language)this.DropDownList1.SelectedIndex;
   //this.LogInOutControl1.ChangeLanguage((Language)this.DropDownList1.SelectedIndex);
  }
 }
}