ASPX – CheckBoxList RequiredFieldValidator

<script type=”text/javascript”>
        function ValidateCheckBoxList(source, args)
        {
            var chkList = document.getElementById(‘<%= lbChangeType.ClientID %>’);
            var chkLista= chkList.getElementsByTagName(“input”);
           
            for(var i=0;i<chkLista.length;i++)
            {  
                if(chkLista[i].checked)
                {
                    args.IsValid = true;
                    return;
                }
            }
           
            args.IsValid = false;
        } 
        </script>