请教一个DropDownList控制Linkbutton的enable问题

Question

有一个DropDownList,一个asp:Linkbutton
        <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" 
            onselectedindexchanged="DropDownList2_SelectedIndexChanged">
            <asp:ListItem Value="1">1</asp:ListItem>
            <asp:ListItem Value="2">2</asp:ListItem>
            <asp:ListItem Value="3">3</asp:ListItem>
        </asp:DropDownList>        <asp:LinkButton ID="LinkButton1" runat="server" CausesValidation="False" 
                Enabled='<%# DropDownList2.SelectedIndex!=0 %>'>首页</asp:LinkButton>现在想要LinkButton的Enabled用服务器端标记<%# DropDownList2.SelectedIndex!=0 %>来判断，可是老是不能让LinkButton的属性变化，请高手帮忙

Answer 1

DropDownList2_SelectedIndexChanged中设置LinkButton 
或通过onchange设置

Answer 2

我的意思是能不能像GridView自定义PagerTemplate中
<asp:LinkButton ID="btnFirst" runat="server" CausesValidation="False" CommandArgument="First" CommandName="Page" Enabled="<%# ((GridView)Container.NamingContainer).PageIndex != 0 %>" Text="首页"></asp:LinkButton>这样去用DownLoadList控制linkbutton的enable

Answer 3

Enabled="<%# GetEnable(Container.NamingContainer)%>"
public bool GetEnable(..

Answer 4

还是不行，我这样写的    
后台
public bool getenable(DropDownList dl)
    {
        if (dl.SelectedIndex == 0)
            return false;
        else
            return true;
    }
前台
     <asp:DropDownList ID="DropDownList3" runat="server" AutoPostBack="True">
         <asp:ListItem Selected="True">1</asp:ListItem>
         <asp:ListItem>2</asp:ListItem>
         <asp:ListItem>3</asp:ListItem>
    </asp:DropDownList>
    <asp:LinkButton ID="LinkButton5" runat="server" Enabled="<%# getenable(DropDownList3)%>">LinkButton</asp:LinkButton>