This example demonstrates how to use image to trigger button for jQuery UI datepicker plugin in asp.net, buttonImage option takes image URL.
Here’s an example
<!DOCTYPE html>
<html>
<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.aspnetcdn.com/ajax/jquery.ui/1.8.10/themes/pepper-grinder/jquery-ui.css"
type="text/css" media="all" />
<script type="text/javascript">
$(function () {
$("#<%= TextBox1.ClientID %>").datepicker({
showOn: "button",
buttonImage: "http://jqueryui.com/demos/datepicker/images/calendar.gif",
buttonImageOnly: true
});
});
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TextBox ID="TextBox1" runat="server">
</asp:TextBox>
</div>
</form>
</body>
</html>
Output

Download
Use-image-to-trigger-button-for-jQuery-UI-datepicker-plugin.zip (1.02 kb)
See live demo