use required field validator for checkbox or checkboxlist

[wdwtest]

<asp:CheckBox ID="CheckBox1" runat="server" />
    
    <asp:RequiredFieldValidator ID="RequiredFieldValidator2" 
        ControlToValidate="CheckBoxList1" runat="server" 
        ErrorMessage="RequiredFieldValidator"></asp:RequiredFieldValidator>

i have used this for checkbox

it gives error as

Control 'CheckBoxList1' referenced by the ControlToValida te property of 'RequiredFieldV alidator2' cannot be validated.

how to use required field validator for checkbox or checkboxlist

[Palyadav]

There are no fields in the check box list to fill , So RequiredFiledVa lidator doesn't work for that control.

You have to use "CustomValidato r" for CheckBoxList... Check this code..

function checkTemp(sender,args)
{
     for(var i=0;i<=document.getElementById("CheckBoxList1").firstChild.children.length-1;i++)
     {
          if(document.getElementById("CheckBoxList1").firstChild.children(i).cells(0).children(0).checked)=='true'
          alert('One is checked')
          args.IsValid=true
          return
                    
     }
     alert('None is selected')
     args.IsValid=false
}


<asp:CustomValidator id="valcheckBoxTemp" runat="server" ClientValidationFunction="checkTemp" ErrorMessage="This is required control "></asp:CustomValidator>