Question

我遇到了验证依赖项控件的问题。如何验证基于dropdownlist（组合框）值的另一个控件。请参阅以下示例。例如：下拉列表有两个值A和B.如果用户选择“A”，则其余字段应成为必填字段，如果用户从下拉列表中选择值“B”，则所有其他字段应成为非必填字段

注意：我正在使用带默认模板的devexpress gridview。

<dx:ASPxGridView ID="ABC" runat="server" AutoGenerateColumns="False"
                    DataSourceID="ABCDataSource" EnableTheming="True"
                     Width="100%" ClientInstanceName="gridABC">
                    <Columns>
                        <dx:GridViewCommandColumn Caption="Actions" ShowInCustomizationForm="True" 
                            VisibleIndex="0">
                            <EditButton Visible="True">
                            </EditButton>
                      </dx:GridViewCommandColumn>
                      <dx:GridViewDataComboBoxColumn Caption="List of Type" FieldName="ListType" 
                            ShowInCustomizationForm="True" VisibleIndex="4" Width="100px">
                            <PropertiesComboBox DataSourceID="ListTypeDataSource" 
                            TextField="ListTypeABC" ValueField="ListTypeABCId" Width="100px">
                            <ValidationSettings>
                                    <RequiredField ErrorText="ListType required" IsRequired="True" />
                          </ValidationSettings>
                          </PropertiesComboBox>
                            <EditFormSettings ColumnSpan="1" VisibleIndex="1" />
                        </dx:GridViewDataComboBoxColumn>
                            <dx:GridViewDataTextColumn Caption="Name"  FieldName="Name" ShowInCustomizationForm="True" 
                            VisibleIndex="2" Width="100px">
                            <PropertiesTextEdit MaxLength="30" Width="100px">
                            <ValidationSettings>
                                    <RequiredField ErrorText="Item Name required" IsRequired="False" />
                          </ValidationSettings>
                            </PropertiesTextEdit>
                            <EditFormSettings ColumnSpan="1" VisibleIndex="2" />
                        </dx:GridViewDataTextColumn>
                        <dx:GridViewDataTextColumn Caption="Contact"  FieldName="Contact" ShowInCustomizationForm="True" 
                            VisibleIndex="3" Width="100px">
                            <PropertiesTextEdit MaxLength="30" Width="100px">
                            <ValidationSettings>
                                    <RequiredField ErrorText="Contact" IsRequired="False" />
                          </ValidationSettings>
                            </PropertiesTextEdit>
                            <EditFormSettings ColumnSpan="1" VisibleIndex="3" />
                        </dx:GridViewDataTextColumn>
                       <Templates>
                        <EditForm>
                            <table>
                                <tr>
                                    <td>`<dx:ASPxGridViewTemplateReplacement ReplacementType="EditFormEditors" ID="ASPxGridViewTemplateReplacement1"
                                            runat="server">
                                            </dx:ASPxGridViewTemplateReplacement>

`

Answer 1

最简单的方法是将DropDownList的AutoPostBack属性设置为true并处理它的SelectedIndexChanged事件。然后你可以在那里启用/禁用验证器。

另一种方法是使用CustomValidator。此验证器不依赖于单个控件。您必须自己编写验证规则。例如ClientValidationFunction：

<script type="text/javascript" >
function ClientValidate(source, arguments)
{
    var txt = document.getElementById('TextBox1');
    var ddl = document.getElementById('DropDownList1');
    var decision = ddl.options[ddl.selectedIndex].text;
    if(decision=='Yes')
    {
        arguments.IsValid = txt.value.length > 0;
    }else{
        arguments.IsValid = true;
    }
}
</script>

<asp:DropDownList id="DropDownList1" runat="server">
<asp:ListItem Selected="True">Yes</asp:ListItem>
<asp:ListItem Selected="False">No</asp:ListItem>
</asp:DropDownList>

<asp:TextBox id="TextBox1" runat="server" />
<asp:Button ID="BtnSubmit" runat="server" Text="Submit" />

<asp:CustomValidator id="CustomValidator1"
   ValidateEmptyText="true"
   ControlToValidate="TextBox1"
   ClientValidationFunction="ClientValidate"
   OnServerValidate="ServerValidation"
   Display="Static"
   ErrorMessage="Please enter text!"
   runat="server"/>

请记住始终实现OnServerValidate，因为您不应该只依赖于javascript（可以禁用）。这很简单：

void ServerValidation(object source, ServerValidateEventArgs args)
{
args.IsValid = DropDownList1.SelectedIndex == 1 || TextBox1.Text.Length > 0;
}

根据下拉选项验证其他控件

1 个答案: