在C#中如何验证RadioButtonList是否被选中？

Question

我有一个RadioButtonList，它是从数据库中获取数据来填充的，用户需要至少勾选/选择其中一个单选按钮。如何确保他们勾选/选择了单选按钮？我尝试了许多不同的方法，但没有成功，这是我的代码。我还试图警告他们未勾选的单选按钮。

我想要做的是验证是否已勾选/选择了RadioButtonList。

    if (cblstatus.SelectedItem.Value == "1")
    {
        //Create Category
        con.Open();
        SqlCommand departament = new SqlCommand("insert into categories(ca_name, ca_number, ca_status, ca_department, ca_date, ca_time, ca_user) " +
        "values('" + category.Text + "', '" + number.Text + "', 'Y', '" + catdepartment.SelectedValue + "', '" + date + "', '" + time + "', '" + user + "')", con);
        departament.ExecuteNonQuery();
        con.Close();
    }
    else if (cblstatus.SelectedItem.Value == "2")
    {
        //Create Category
        con.Open();
        SqlCommand departament = new SqlCommand("insert into categories(ca_name, ca_number, ca_status, ca_department, ca_date, ca_time, ca_user) " +
        "values('" + category.Text + "', '" + number.Text + "', 'N', '" + catdepartment.SelectedValue + "', '" + date + "', '" + time + "', '" + user + "')", con);
        departament.ExecuteNonQuery();
        con.Close();
    }
    else if (cblstatus. == null)
    {
        alert.InnerHtml = "<div id=\"warning\" class=\"message warning\">Warning! Please select a department.</div>" +
        "<script>" +
            "setTimeout(function () { $('#success').fadeOut(); }, 2000);" +
        "</script>";
    }

- jorame

Answer 1

不要在代码后台执行此操作，而是使用ASP.NET必填字段验证器：

以下是一个示例：

<asp:RadioButtonList runat="server" ID="gender" RepeatDirection="Horizontal"  RepeatLayout="Flow" CssClass="labels">
<asp:ListItem Text="Male" Value="Male"></asp:ListItem>
<asp:ListItem Text="Female" Value="Female"></asp:ListItem>

<asp:RequiredFieldValidator runat="server" ID="genderRequired" Display="Dynamic"
    ControlToValidate="gender" ErrorMessage="This is an Error"
    ValidationGroup="signUp">*</asp:RequiredFieldValidator>

在代码后台，您可以创建一个空的

元素，然后在错误时向其添加文本，并使用jQuery的change函数进一步操作它：

if (gender.SelectedItem.Value == "Male") 
{

    //do stuff
}

else if (gender.SelectedItem.Value == "Female")
{
    //do stuff
}

else 
{
    errorDiv.InnerText = "Error Messeage";
}

http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.requiredfieldvalidator.aspx

- Wahtever

---

是的，您也可以在服务器端使用它进行验证，您只需要将 EnableClientScript="False" 参数添加到 RequiredFieldValidator 中，并在服务器端使用 if(genderRequired.IsValid){...}。如果我正确理解了问题的话... - Roise

Answer 2

我们可以使用普通的RequiredFieldValidation而不定义InitialValue属性。

<asp:RadioButtonList runat="server" ID="Radioyesno" RepeatDirection="Horizontal">
 <asp:ListItem>Yes</asp:ListItem>
 <asp:ListItem>No</asp:ListItem>
</asp:RadioButtonList>
<asp:RequiredFieldValidator runat="server" ID="RFV123" ValidationGroup="VG1" ControlToValidate="Radioyes" ErrorMessage="PLEASE SELECT YES/NO"/>

对我来说它有效，没有复杂的思考

- Syed Mohamed

Answer 3

可以采用这种方法，但完全是在代码后端实现的。

 public bool ValidateRadioButtonList()
{
    bool rbchecked= false;
    for (int i = 0; i < RadioButtonList1.Items.Count - 1; i++)
    {
        if (RadioButtonList1.Items[i].Selected==true)
        {
            rbchecked = true;
        }
    }
    if (rbchecked == true)
    {
        lblError.Text = string.Empty;
        return true;
    }
    else
    {
        lblError.Text = "Please select RadioButton!";
        return false;
    }
}

- Vijay Kumbhoje

Answer 4

.aspx：

<asp:RadioButtonList ID="rbAny" runat="server" >
 <asp:ListItem Value="rb1" Text="something1"></asp:ListItem>
 <asp:ListItem Value="rb2" Text="something2"></asp:ListItem>
 <asp:ListItem Value="rb3" Text="something3"></asp:ListItem>
</asp:RadioButtonList>

.aspx.cs：

在ViewState中添加/插入值（例如通过单击按钮）：

protected void btnSend_Click(object sender, EventArgs e)
{
    foreach (ListItem r in rbAny.Items) 
        if (r.Selected) ViewState["anyValue"] = r.Text;
}

从ViewState中读取值：

protected void btnShow_Click(object sender, EventArgs e)
{
    StringBuilder str = new StringBuilder();
    str.Append("anyValue: " + ViewState["anyValue"]);
    someLabel.Text = str.ToString();
}

- helavin4ik

Answer 5

Imports System.IO
Imports System.Text
Imports System


Public Class WebForm1
    Inherits System.Web.UI.Page



    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    End Sub

    'Protected Sub Calendar1_SelectionChanged(sender As Object, e As EventArgs)

    '    TextBox1.Text = Calendar1.SelectedDate.ToShortDateString()
    '    Calendar1.Visible = False












    'End Sub

    'Protected Sub LinkButton1_Click(sender As Object, e As EventArgs)
    '    'Calendar1.Visible = True


    'End Sub

    'Protected Sub LinkButton2_Click(sender As Object, e As EventArgs)
    '    Calendar2.Visible = True
    'End Sub

    'Protected Sub Calendar2_SelectionChanged(sender As Object, e As EventArgs)
    '    TextBox2.Text = Calendar2.SelectedDate.ToShortDateString()
    '    Calendar2.Visible = False
    'End Sub

    Public Sub DownloadCSV()
        Dim csvPath1 As String = "D:\CSVFile1.csv"

        'Download and read all Text within the uploaded Text file.
        Dim csvContentStr1 As String = File.ReadAllText(csvPath1)

        Dim split As String() = csvContentStr1.Split(","c)

        'Here you can see the output as CSV content.
        'Response.Write(csvContentStr)
    End Sub


    Public Sub UploadCSV()
        Dim csvContent As New StringBuilder()

        DownloadCSV()

        Dim dt1 As DateTime = Convert.ToDateTime(TextBox1.Text)
        Dim dt2 As DateTime = Convert.ToDateTime(TextBox2.Text)
        Dim dt3 As TimeSpan = dt2.Subtract(dt1)
        Dim NoOfDays As Integer = dt3.Days + 1
        'TextBox3.Text = NoOfDays.ToString

        Dim index As DateTime = Convert.ToDateTime(TextBox1.Text)
        While index <= Convert.ToDateTime(TextBox2.Text)
            If index.DayOfWeek = DayOfWeek.Saturday OrElse index.DayOfWeek = DayOfWeek.Sunday Then
                NoOfDays = NoOfDays - 1
            End If
            index = index.AddDays(1)

        End While

        Dim a1 As String = TextBox1.ToString()
        Dim b1 As String = TextBox2.ToString()
        Dim c1 As String = RadioButtonList1.Text.ToString()
        Dim d1 As String = TextBox3.ToString()

        Dim z1 As String = TextBox1.Text + "," + TextBox2.Text + "," + RadioButtonList1.Text + "," + TextBox3.Text + "," + NoOfDays.ToString

        'csvContent.AppendLine("From Date,To Date,Laeve Type,Reason")
        csvContent.AppendLine(z1)

        Dim csvPath As String = "D:\CSVFile2.csv"

        ' Save or upload CSV format File (.csv)
        File.AppendAllText(csvPath, csvContent.ToString())
    End Sub


    Protected Sub Button1_Click(sender As Object, e As EventArgs)








        If Page.IsValid Then
            Dim a1 As String = TextBox1.ToString()
            Dim b1 As String = TextBox2.ToString()
            Dim c1 As String = RadioButtonList1.Text.ToString()
            Dim d1 As String = TextBox3.ToString()





            UploadCSV()
            DownloadCSV()


        End If




    End Sub

    Protected Sub Button2_Click(sender As Object, e As EventArgs)

    End Sub








End Class

Aspx代码

<%@ Page Title="" Language="vb" AutoEventWireup="false" MasterPageFile="~/Site1.Master" CodeBehind="WebForm1.aspx.vb" Inherits="Leave12.WebForm1" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">

   <table>

       <tr>
          <%-- <td>
               <asp:LinkButton ID="LinkButton1" runat="server" OnClick="LinkButton1_Click" >Select From Date.....</asp:LinkButton>
           </td>
           <td>
               <asp:Calendar ID="Calendar1" runat="server" Visible="false" OnSelectionChanged="Calendar1_SelectionChanged" ></asp:Calendar>
           </td>
           <td>
               <asp:TextBox ID="TextBox1" ReadOnly="true" runat="server"></asp:TextBox>
           </td>--%>

           <td>
           <asp:Label ID="Label1" runat="server" Text="Please enter From Date"></asp:Label>
          </td>
           <td>
               <asp:TextBox ID="TextBox1" TextMode="Date" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ErrorMessage="Please enter From Date" Display="Dynamic" ControlToValidate="TextBox1"></asp:RequiredFieldValidator>
           </td>

       </tr>
       <tr>
          <%-- <td>
               <asp:LinkButton ID="LinkButton2" runat="server" OnClick="LinkButton2_Click">Select To Date.....</asp:LinkButton>
           </td>
           <td>
               <asp:Calendar ID="Calendar2" runat="server" Visible="false" OnSelectionChanged="Calendar2_SelectionChanged" ></asp:Calendar>
           </td>
           <td>
               <asp:TextBox ID="TextBox2" ReadOnly="true" runat="server"></asp:TextBox>
           </td>--%>

           <%--<td>
               <asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" ErrorMessage="Please enter To Date" Display="Dynamic" ControlToValidate="TextBox2"></asp:RequiredFieldValidator>
           </td>--%>
           <td>
               <asp:Label ID="Label2" runat="server" Text="Please enter To Date"></asp:Label>
           </td>
           <td>
               <asp:TextBox ID="TextBox2" TextMode="Date" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" ErrorMessage="Please enter To Date" Display="Dynamic" ControlToValidate="TextBox2"></asp:RequiredFieldValidator>
           </td>
           <td>
               <asp:CompareValidator ID="CompareValidator1" runat="server" ErrorMessage="To Date should be greater than From Date" Display="Dynamic" Operator="GreaterThanEqual" ControlToCompare="TextBox1" ControlToValidate="TextBox2"></asp:CompareValidator>
           </td>

       </tr>
       <tr>

           <td>
               <asp:Label ID="Label3" runat="server" Text="Please select Leave Type"></asp:Label>
           </td>
           <td>
               <asp:RadioButtonList RepeatDirection="Horizontal" ID="RadioButtonList1"   runat="server" >
                   <asp:ListItem Selected="True" >Casual Leave</asp:ListItem>
                   <asp:ListItem>Sick Leave</asp:ListItem>
                   <asp:ListItem>Earned Leave</asp:ListItem>
               </asp:RadioButtonList>




           </td>



       </tr>
       <%--<tr>
           <td>
               <asp:Label ID="Label2" runat="server" Text="Reason"></asp:Label>
           </td>
           <td>
               <asp:TextBox ID="TextBox3" TextMode="MultiLine" Rows="5" Columns="50" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server" ErrorMessage="Please select Reason" ControlToValidate="TextBox3" Display="Dynamic"></asp:RequiredFieldValidator>
           </td>
       </tr>--%>
       <tr>
           <td>
               <asp:Label ID="Label4" runat="server" Text="Reason"></asp:Label>
           </td>
           <td>
               <asp:TextBox ID="TextBox3" TextMode="MultiLine" MaxLength="250" Rows="5" Columns="50" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" ErrorMessage="Please provide reason for leave" Display="Dynamic" ControlToValidate="TextBox3"></asp:RequiredFieldValidator>
           </td>
           <td>
               <asp:RegularExpressionValidator ID="RegularExpressionValidator1" ValidationExpression="^[\s\S]{0,100}$" runat="server" ErrorMessage="Please enter maximum of 250 characters" Display="Dynamic" ControlToValidate="TextBox3"></asp:RegularExpressionValidator>
           </td>
       </tr>
       <tr>
           <td>
               <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Submit" />
           </td>
           <td>
               <asp:Button ID="Button2" runat="server" OnClick="Button2_Click" Text="Reset" />
           </td>
       </tr>


   </table>
</asp:Content>

- John