DropDownList的SelectedIndexChanged事件不能激发

Question

   <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True">
                        <asp:ListItem>已</asp:ListItem>
                        <asp:ListItem>未</asp:ListItem>
                    </asp:DropDownList>
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (DropDownList1.SelectedValue== "已")
        { Panel1.Visible = true; Panel2.Visible = false; }
        else
        { Panel2.Visible = true; Panel1.Visible = false; }
    }如题如代码，哪里问题

Answer 1

本帖最后由 net_lover 于 2011-08-24 11:04:53 编辑

  

Answer 2

<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
                        <asp:ListItem>已</asp:ListItem>
                        <asp:ListItem>未</asp:ListItem>
                    </asp:DropDownList>
加上事件名