VB.NET-如何防止自动回发从表单中清除输入的数据

背景：我有一个web表单，可以根据选择的运营商将捆绑包列表回发到列表框。回发时，所有用户输入的数据都将被清除

                    <asp:RequiredFieldValidator ID="CarrierValidator" runat="server" Text="*"
                        ErrorMessage="Select At Least 1 Carrier"  ControlToValidate="lbCarriers"
                        ValidationGroup = "ValidationGroup" ForeColor="Red" ></asp:RequiredFieldValidator>

        </td>
    </tr>
            <tr>
        <td class="style1">
            Bundles:<br />
            <font size="1">*Hold Ctrl Key Down to Select Multiple Bundles</font></td>
        <td bgcolor="#ffffff" class="style6">
            <asp:ListBox ID="bundles" SelectionMode="Multiple" runat="server" Height="86px" 
                Width="250px" Enabled="True" 
                ValidationGroup="ValidationGroup">
            </asp:ListBox>

如何防止自动回邮功能从表单中清除输入的数据

                    <asp:RequiredFieldValidator ID="CarrierValidator" runat="server" Text="*"
                        ErrorMessage="Select At Least 1 Carrier"  ControlToValidate="lbCarriers"
                        ValidationGroup = "ValidationGroup" ForeColor="Red" ></asp:RequiredFieldValidator>

        </td>
    </tr>
            <tr>
        <td class="style1">
            Bundles:<br />
            <font size="1">*Hold Ctrl Key Down to Select Multiple Bundles</font></td>
        <td bgcolor="#ffffff" class="style6">
            <asp:ListBox ID="bundles" SelectionMode="Multiple" runat="server" Height="86px" 
                Width="250px" Enabled="True" 
                ValidationGroup="ValidationGroup">
            </asp:ListBox>

以下是该应用程序的屏幕截图：

                    <asp:RequiredFieldValidator ID="CarrierValidator" runat="server" Text="*"
                        ErrorMessage="Select At Least 1 Carrier"  ControlToValidate="lbCarriers"
                        ValidationGroup = "ValidationGroup" ForeColor="Red" ></asp:RequiredFieldValidator>

        </td>
    </tr>
            <tr>
        <td class="style1">
            Bundles:<br />
            <font size="1">*Hold Ctrl Key Down to Select Multiple Bundles</font></td>
        <td bgcolor="#ffffff" class="style6">
            <asp:ListBox ID="bundles" SelectionMode="Multiple" runat="server" Height="86px" 
                Width="250px" Enabled="True" 
                ValidationGroup="ValidationGroup">
            </asp:ListBox>

                    <asp:RequiredFieldValidator ID="CarrierValidator" runat="server" Text="*"
                        ErrorMessage="Select At Least 1 Carrier"  ControlToValidate="lbCarriers"
                        ValidationGroup = "ValidationGroup" ForeColor="Red" ></asp:RequiredFieldValidator>

        </td>
    </tr>
            <tr>
        <td class="style1">
            Bundles:<br />
            <font size="1">*Hold Ctrl Key Down to Select Multiple Bundles</font></td>
        <td bgcolor="#ffffff" class="style6">
            <asp:ListBox ID="bundles" SelectionMode="Multiple" runat="server" Height="86px" 
                Width="250px" Enabled="True" 
                ValidationGroup="ValidationGroup">
            </asp:ListBox>

asp前端代码：

                    <asp:RequiredFieldValidator ID="CarrierValidator" runat="server" Text="*"
                        ErrorMessage="Select At Least 1 Carrier"  ControlToValidate="lbCarriers"
                        ValidationGroup = "ValidationGroup" ForeColor="Red" ></asp:RequiredFieldValidator>

        </td>
    </tr>
            <tr>
        <td class="style1">
            Bundles:<br />
            <font size="1">*Hold Ctrl Key Down to Select Multiple Bundles</font></td>
        <td bgcolor="#ffffff" class="style6">
            <asp:ListBox ID="bundles" SelectionMode="Multiple" runat="server" Height="86px" 
                Width="250px" Enabled="True" 
                ValidationGroup="ValidationGroup">
            </asp:ListBox>

                    <asp:RequiredFieldValidator ID="CarrierValidator" runat="server" Text="*"
                        ErrorMessage="Select At Least 1 Carrier"  ControlToValidate="lbCarriers"
                        ValidationGroup = "ValidationGroup" ForeColor="Red" ></asp:RequiredFieldValidator>

        </td>
    </tr>
            <tr>
        <td class="style1">
            Bundles:<br />
            <font size="1">*Hold Ctrl Key Down to Select Multiple Bundles</font></td>
        <td bgcolor="#ffffff" class="style6">
            <asp:ListBox ID="bundles" SelectionMode="Multiple" runat="server" Height="86px" 
                Width="250px" Enabled="True" 
                ValidationGroup="ValidationGroup">
            </asp:ListBox>

---

谢谢你的关注

您的控件是动态构建的吗？如果没有，只需启用viewstate。

谢谢您的回复！如何检查控件是否是动态构建的，您是否有启用wiewstate的代码示例？

                    <asp:RequiredFieldValidator ID="CarrierValidator" runat="server" Text="*"
                        ErrorMessage="Select At Least 1 Carrier"  ControlToValidate="lbCarriers"
                        ValidationGroup = "ValidationGroup" ForeColor="Red" ></asp:RequiredFieldValidator>

        </td>
    </tr>
            <tr>
        <td class="style1">
            Bundles:<br />
            <font size="1">*Hold Ctrl Key Down to Select Multiple Bundles</font></td>
        <td bgcolor="#ffffff" class="style6">
            <asp:ListBox ID="bundles" SelectionMode="Multiple" runat="server" Height="86px" 
                Width="250px" Enabled="True" 
                ValidationGroup="ValidationGroup">
            </asp:ListBox>