Question

所以，我有这个更新面板：

<asp:UpdatePanel runat="server" RenderMode="Inline" UpdateMode="Conditional">

    <Triggers>
        <asp:AsyncPostBackTrigger ControlID="btnSubmit" EventName="Click" />
        <asp:AsyncPostBackTrigger ControlID="ddOutcomeType" />
        <asp:AsyncPostBackTrigger ControlID="ddOutcomeCode" />
    </Triggers>

    <ContentTemplate>
        <fieldset>

            <asp:DropDownList ID="ddOutcomeType" runat="server" AutoPostBack="True" 
                 OnSelectedIndexChanged="ddOutcomeType_OnSelectedIndexChanged">
                <asp:ListItem Value="0">Please Select...</asp:ListItem>
                <asp:ListItem Value="EDU">Continuing in Education</asp:ListItem>
                <asp:ListItem Value="EMP">Paid Employment</asp:ListItem>
                <asp:ListItem Value="NPE">Not in Paid Employment</asp:ListItem>
                <asp:ListItem Value="GAP">Gap Year</asp:ListItem>
                <asp:ListItem Value="OTH">Other</asp:ListItem>
            </asp:DropDownList>

            <asp:DropDownList ID="ddOutcomeCode" runat="server" DataTextField="COMPDESC" 
                 DataValueField="EBSVALUE" 
                 OnSelectedIndexChanged="ddOutcomeCode_OnSelectedIndexChanged"
                 AutoPostBack="True" Visible="false" />

            <br /><br />
            <asp:Label ID="lblDestMessage" runat="server" 
                 Text="Please start typing at least 3 characters of the HE institute 
                       then select from the list (Don't make your own up!)" 
                 Visible="false">
            </asp:Label>

            &nbsp;&nbsp;&nbsp;&nbsp;

            <h4 style="align-content:center;">
            <asp:Label ID="Label1" runat="server" Text="Comments on Destination">
            </asp:Label></h4>
            <asp:TextBox ID="txtDestComments" runat="server" Width="70%"></asp:TextBox>
            <br />
            <asp:RegularExpressionValidator ID="validJust" runat="server" 
                 Display="Dynamic" ControlToValidate="txtDestComments" 
                 ValidationExpression="^([\S\s]{0,249})$" CssClass="label label-danger" 
                 ErrorMessage="Please enter maximum 250 characters" 
                 SetFocusOnError="True">
            </asp:RegularExpressionValidator>
            <br />



            <asp:Button ID="btnSubmit" runat="server" Text="Submit" 
                 CssClass="btn btn-primary" OnClick="btnSubmit_OnClick" />

        </fieldset>
    </ContentTemplate>
</asp:UpdatePanel>

我已针对同一问题查看了其他问题，但没有任何修复工作，我尝试将按钮放在更新面板之外，但是下拉列表更改的隐藏字段不会保持更改更新面板。

任何帮助？

Answer 1

您正在使用更新面板的UpdateMode属性作为UpdateMode =＆＃34;条件＆＃34;。要么必须在服务器端的按钮Click事件中显式使用更新面板的Update（）方法来更新更新面板内的内容，要么删除此UpdateMode属性，因为默认设置为Always。

按钮未在更新面板内触发，查看其他问题且没有任何修复工作

1 个答案: