In this example you will see how to integrate jQuery UI Datepicker pop up calendar with asp.net textbox control, I have used Google CDN jQuery UI and CSS style sheet file.
Here’s an example
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.7.min.js" type="text/javascript"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.16/jquery-ui.js" type="text/javascript"></script>
<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.16/themes/base/jquery-ui.css" type="text/css" media="all" />
<script type="text/javascript">
$(function () {
$("#<%= TextBox1.ClientID %>").datepicker();
});
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</div>
</form>
</body>
</html>
Output

Download
jQueryUI-datepicker.zip (968.00 bytes)
See live demo