<%@ Page Language="C#" %>
<%@ Import namespace="System.Text" %>
<script runat="server">
void Page_load(object sender, EventArgs e)
{
Button1.Attributes.Add( "onclick", "popWin()" );
}
</script>
<html>
<head>
<script>
function popWin()
{
window.open('yourpage.aspx");
}
</script>
</head>
<body>
<form runat="server">
<asp:Button id="Button1" onclick="Button1_Click" runat="server" Text="Go!">
</form>
</body>
</html>
or we can try this
Page load. (C#)
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
string url = "yourpage_to_open.aspx?querystrings=23";
Button1.Attributes.Add("onclick", "window.open('" + url + "', '_blank', 'height=500,width=800,status=yes,toolbar=no,menubar=no,location=no,scrollbars=yes,resizable=no,titlebar=no' );return false;");
}
}
ASPX
<!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>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:Button ID="Button1" runat="server" Text="Button" />
</div>
</form>
</body>
</html>