<script type="text/javascript">
function checkDate(sender, args) {
var toDate= new Date();
toDate.setMinutes(0);
toDate.setSeconds(0);
toDate.setHours(0);
toDate.setMilliseconds(0);
if ( sender._selectedDate < toDate) {
alert("You can't select day earlier than today!");
sender._selectedDate = toDate;
sender._textbox.set_Value(sender._selectedDate.format(sender._format))
}
}
</script></script>