<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<meta name="viewport" content="width=device-width, initial-scale=1" />
<meta content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" name="viewport" />
<title></title>
<style type="text/css">
.auto-style1 {
height: 2680px;
}
</style>
</head>
<body style="background-color:aliceblue">
<form id="form1" runat="server">
<div class="auto-style1">
</div>
<!--把div放在这个位置就好了 begin-->
<div id="dg" runat="server" style="z-index: 9999; position: fixed ! important; right: 10px; top: 10px;">
<table style="position: absolute; width:260px; right: 0px; top: 0px;">
<asp:imageButton runat="server" ImageUrl="~/image/home.png" Width="48px" Height="50px" OnClick="Unnamed1_Click"></asp:imageButton>
</table>
</div>
<!--把div放在这个位置就好了 end-->
</form>
</body>
</html>
原文：https://www.cnblogs.com/yangsongyan/p/11176238.html