asp.net - 必填字段验证在 asp.net 中不起作用

Question

我需要一个单选按钮列表的字段验证控件。因此，如果没有选择任何值，那么它会给我一个错误，这很好。但是当我重做选择某些东西并单击按钮时，它不会触发按钮的服务器事件。一旦我有验证错误，那么无论我做什么都会禁用服务器端事件。任何想法为什么会发生我的代码

<div id="studysub_popul" runat="server" visible="false">
   <asp:Label ID="lbl_rdb_study_popul" runat="server"
              CssClass="questions"
              Text="2.Select your study subjects">
   </asp:Label>

   <asp:RadioButtonList ID="rdb_study_popul" runat="server"
                        AutoPostBack="True" 
                        OnSelectedIndexChanged="rdb_study_popul_SelectedIndexChanged">
     <asp:ListItem>Individuals</asp:ListItem>
     <asp:ListItem>Population</asp:ListItem>
   </asp:RadioButtonList>

   <asp:RequiredFieldValidator ID="RequiredFieldValidator5" runat="server" 
                                ControlToValidate="rdb_study_popul"
                                Display="Dynamic" 
                                ErrorMessage="Study Subject is required" 
                                ValidationGroup="StudySubject">
   </asp:RequiredFieldValidator>
                        </div>
                    </td>
                </tr>
                <tr>
        <td>
    <asp:Button ID="btn_s_section" runat="server"  
                OnClick="btn_studysubject_section_Click"
                Text="Next" ValidationGroup="StudySubject"
                Visible="false" />
       </td>

Answer 1

您也应该向 RadioButtonList 定义添加一个验证组。

   <asp:RadioButtonList ID="rdb_study_popul" runat="server"
                        AutoPostBack="True" 
                        OnSelectedIndexChanged="rdb_study_popul_SelectedIndexChanged"
                        ValidationGroup="StudySubject">