download xml file using asp.net

<asp:linkbutton id="lb_DownloadXML" runat="server" text="Download file" onclick="lb_DownloadXML_Click" xmlns:asp="#unknown"></asp:linkbutton>

protected void lb_DownloadXML_Click(object sender, EventArgs e)
    {
        string strFullPath = Server.MapPath("~/temp.xml");        
        string strContents = null;
        System.IO.StreamReader objReader = default(System.IO.StreamReader);
        objReader = new System.IO.StreamReader(strFullPath);
        strContents = objReader.ReadToEnd();
        objReader.Close();

        string attachment = "attachment; filename=test.xml";
        Response.ClearContent();
        Response.ContentType = "application/xml";
        Response.AddHeader("content-disposition", attachment);
        Response.Write(strContents);
        Response.End();        
    }