asp.net的控件login，在后台Login1.UserName总为空？？

Question

这是怎么回事呀？？？
Login1_LoginError
Login1_Authenticate
我在这两个事件下获得Login1.UserName值都是空
急呀！！！！

Answer 1

    <asp:Login ID="Login1" runat="server" CreateUserText="还没有账户" PasswordRecoveryUrl="PasswordRecovery.aspx"
        PasswordRecoveryText="找回密码" 
        DestinationPageUrl="../Default.aspx" onloginerror="Login1_LoginError" 
    onauthenticate="Login1_Authenticate" >
        <LayoutTemplate>
            <table class="tab_info">
                <tr>
                    <td colspan="2" class="tab_title">
                        登 录
                    </td>
                </tr>
                <tr>
                    <td style="width: 30%;">
                        &nbsp;<asp:Label ID="UserNameLabel" runat="server" AssociatedControlID="UserName">用户名</asp:Label>
                    </td>
                    <td style="width: 70%;">
                        &nbsp;
                        <asp:TextBox ID="UserName" Width="150px" runat="server" Text="440402197505016111"></asp:TextBox>
                        <asp:RequiredFieldValidator ID="UserNameRequired" runat="server" ControlToValidate="UserName"
                            ErrorMessage="必须填写“用户名”。" ToolTip="必须填写“用户名”。" ValidationGroup="Login1">*</asp:RequiredFieldValidator>
                    </td>
                </tr>
                <tr>
                    <td>
                        &nbsp;<asp:Label ID="PasswordLabel" runat="server" AssociatedControlID="Password">密&nbsp;&nbsp;&nbsp;&nbsp;码</asp:Label>
                    </td>
                    <td>
                        &nbsp;
                        <asp:TextBox ID="Password" Width="150px" runat="server" TextMode="Password"></asp:TextBox>
                        <asp:RequiredFieldValidator ID="PasswordRequired" runat="server" ControlToValidate="Password"
                            ErrorMessage="必须填写“密码”。" ToolTip="必须填写“密码”。" ValidationGroup="Login1">*</asp:RequiredFieldValidator>
                    </td>
                </tr>
                <tr>
                    <td>
                        &nbsp;<asp:Label ID="Label1" runat="server">验证码</asp:Label>
                    </td>
                    <td>
                        &nbsp;
                        <asp:TextBox ID="TxtValidateNumber" Width="50px" runat="server" AutoCompleteType="Disabled"></asp:TextBox>
                        <asp:Image ID="Image1" runat="server" ImageUrl="../images/VldNum.aspx" ImageAlign="Top"
                            alt="看不清？点击更换" onclick="this.src=this.src+'?'" />
                        <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="TxtValidateNumber"
                            ErrorMessage="必须填写“验证码”。" ValidationGroup="Login1" Display="Dynamic">*</asp:RequiredFieldValidator>
                        <asp:CustomValidator ID="CustomValidator1" runat="server" ErrorMessage="“验证码”错误。"
                            ControlToValidate="TxtValidateNumber" OnServerValidate="CustomValidator1_ServerValidate"
                            ValidationGroup="Login1" Display="Dynamic">*</asp:CustomValidator>
                    </td>
                </tr>
                <tr>
                    <td colspan="2">
                        <center>
                            <asp:Button ID="LoginButton" runat="server" CommandName="Login" Text="登 录" ValidationGroup="Login1" />
                            <asp:CheckBox ID="RememberMe" runat="server" Text="记住我" />
                        </center>
                    </td>
                </tr>
                <tr>
                    <td colspan="2">
                        <asp:HyperLink ID="PasswordRecoveryLink" runat="server" NavigateUrl="PasswordRecovery.aspx">密码重置</asp:HyperLink>
                    </td>
                </tr>
                <tr>
                    <td colspan="2" style="color: Red;">
                        <asp:ValidationSummary ID="ValidationSummary1" ValidationGroup="Login1" Display="Dynamic"
                            runat="server" />
                        <asp:Literal ID="FailureText" runat="server" EnableViewState="False"></asp:Literal>
                    </td>
                </tr>
            </table>
        </LayoutTemplate>
    </asp:Login>

Answer 2

登陆成功之后必须设置一个成功标志的cookie