Hi
Try this code..
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm2.aspx.cs" Inherits="POC.WebForm2" %>
<!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 id="Head1" runat="server">
<title></title>
<script src="JQuery.js" type="text/javascript"></script>
<script type="text/javascript">
$(function () {
$('<div id="mydiv"></div>').css({ 'height': '100px', 'width': '100px', 'background-color': 'green' }).appendTo('#form1');
$('#btnhide').click(function () {
$('#mydiv').hide('slow'); return false;
});
$('#btnshow').click(function () {
$('#mydiv').show('slow'); return false;
});
});
</script>
</head>
<body>
<form id="form1" runat="server">
<asp:Button ID="btnhide" runat="server" Text="Hide" />
<asp:Button ID="btnshow" runat="server" Text="Show" />
</form>
</body>
</html>