<asp:CheckBoxList ID="OrganizationTypesList" RepeatColumns="2" RepeatDirection="Horizontal" DataSourceID="OrganizationTypesDatasource" DataTextField="TypeName" DataValueField="OutreachOrganizationTypeID" runat="server" />
<asp:CustomValidator runat="server" id="CVOrgTypelist" ClientValidationFunction="ValidateCheckBoxList" ValidateEmptyText="true"
ErrorMessage="Select Atleast one Organization Type" ValidationGroup="ParentValidation" Display="Dynamic" />
<script type="text/javascript">
function ValidateCheckBoxList(sender, args) {
args.IsValid = false;
alert("in");
jQuery(".CheckBoxList").find(":checkbox").each(function () {
if (jQuery(this).attr("checked")) {
alert("valid");
args.IsValid = ...
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