textbox validation Using JQuery

<script language="javascript" type="text/javascript">
$(document).ready(function ()
{
$("#<% =btnSubmit.ClientID %>").click(function ()
{
if (jQuery.trim($("#<%=txtBranchCode.ClientID %>").val()) == "")
{
alert("Please enter branch code..");
$("#<%=txtBranchCode.ClientID %>").focus();
return false;
} });
$("#<% =btnCancel.ClientID %>").click(function ()
{
$("#<%=txtBranchCode.ClientID %>").val("");
return false;
});
});
</script>