更改標籤文本不工作時的UpdatePanel

Question

之外下面我有一個列表框代碼：

<asp:UpdatePanel ID="UpdatePanel1" runat="server"> 
    <ContentTemplate> 
    <asp:ListBox ID="ListBox1" runat="server" onselectedindexchanged="ListBox1_SelectedIndexChanged" AutoPostBack="True"> 
    <asp:ListItem Value="0">Item1</asp:ListItem> 
    <asp:ListItem Value="1">Item2</asp:ListItem> 
    <asp:ListItem Value="2">Item3</asp:ListItem> 
    </asp:ListBox> 
</ContentTemplate> 
</asp:UpdatePanel> 

<br /> 
<asp:Label ID="lblTB" runat="server"/> 

這是該指數改變了事件背後的代碼：

protected void ListBox1_SelectedIndexChanged(object sender, EventArgs e) 
{ 
    lblTB.Text = "You choose: " + ListBox1.SelectedItem.Text; 
} 

我不想將控制標籤放入UpdatePanel。我怎樣才能讓這段代碼運行？謝謝大家。

Answer 1

代碼看起來很好，只是添加ScriptManager。嘗試這樣的：

 <asp:ScriptManager runat="server"></asp:ScriptManager> 
     <asp:UpdatePanel ID="UpdatePanel1" runat="server"> 
     <ContentTemplate> 
     <asp:ListBox ID="ListBox1" runat="server" 
onselectedindexchanged="ListBox1_SelectedIndexChanged" AutoPostBack="True"> 
     <asp:ListItem Value="0">Item1</asp:ListItem> 
     <asp:ListItem Value="1">Item2</asp:ListItem> 
     <asp:ListItem Value="2">Item3</asp:ListItem> 
     </asp:ListBox> 
     </ContentTemplate> 
     </asp:UpdatePanel> 
     <asp:Label ID="lblTB" runat="server"/> 

後面的代碼應該是。

try 
    { 
     HttpCookie getcook = Request.Cookies["saveme"]; 
     string check = getcook["saveme"].ToString(); 
     if (getcook["saveme"].Length > 0 &&  getcook["saveme"].ToString()!="none") 
      { 
      lblTB.Text = getcook["saveme"].ToString(); 
      } 
     } 
     catch(Exception er) 
     { 
      HttpCookie cookie = new HttpCookie("saveme"); 
      cookie["saveme"] = "none"; 
      Response.Cookies.Add(cookie); 

     } 

    } 

    protected void ListBox1_SelectedIndexChanged(object sender, EventArgs e) 
    { 
     lblTB.Text = "You choose: " + ListBox1.SelectedItem.Text; 
     HttpCookie setcook =Request.Cookies["saveme"]; 
     setcook["saveme"] = lblTB.Text; 
     setcook.Expires = DateTime.Now.AddDays(1d); ; 
     Response.Cookies.Add(setcook); 
     Response.Redirect("updatepanelhere.aspx", false); 
    }