protected void Page_PreInit(object sender, System.EventArgs e)        {            if (IsPostBack)            {                //Label1.Text += "Page.PreInti Event
";            }        }        protected void Page_Init(object sengder, EventArgs e)        {            Label1.Text += "Page.Init Event
";        }        protected void Page_InitComplete(object sender, EventArgs e)        {            Label1.Text += "Page.InitComplete
";        }        protected void Page_PreLoad(object sender, EventArgs e)        {            Label1.Text += "Page.PreLoad Event
";        }        protected void Page_Load(object sender, EventArgs e)        {            Label1.Text += "Page.Load Event
";            if (Page.IsPostBack)            {                Label1.Text += "Send back request
";            }        }        protected void Page_LoadComplete(object sender, EventArgs e)        {            Label1.Text += "Page.LoadComplete Event
";        }        protected void Page_PreRender(object sender, EventArgs e)        {            Label1.Text += "Page.PreRender Event
";        }        protected void Page_Render(object sender, EventArgs e)        {            Label1.Text += "Page.Render Event";        }        protected void Page_Unload(object sender, EventArgs e)        {            //Label1.Text += "Page.Unload Event
";        }        protected void Button1_Click(object sender, EventArgs e)        {            Label1.Text += "Button.Click Event
";        }

　　http://msdn.microsoft.com/zh-cn/library/ms178472.aspx#general_page_lifecycle_stages