<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet"
href="http://code.jquery.com/ui/1.9.2/themes/base/jquery-ui.css" />
<script src="http://code.jquery.com/jquery-1.8.3.js"></script>
<script src="http://code.jquery.com/ui/1.9.2/jquery-ui.js"></script>
<script>
$(function(){
$('#calendar').datepicker({
dateFormat: "yy-mm-dd",
onSelect: function(selectedDate){
$.get('/doSomething.php', {date: selectedDate}, function(result){
alert(result);
});
}
});
});
</script>
</head>
<body>
<div id="calendar"></div>
</body>
</html>