Export ASP.Net Chart to Excel and PowerPoint files

Hi  sir how to export ASP.net chartcontrol to Excel and ppt,

For exporting excel i tried different ways...

Below is my codeits not working

 protected void Button2_Click(object sender, EventArgs e)
    {
        Response.Clear();
        Response.Buffer = true;
        Response.AddHeader("content-disposition",
         "attachment;filename=GridViewExport.xls");
        Response.Charset = "";
        Response.ContentType = "application/vnd.ms-excel";
        StringWriter sw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(sw);


        Chart1.RenderControl(hw);
        //style to format numbers to string
        string style = @"<style> .textmode { mso-number-format:\@; } </style>";
        Response.Write(style);
        Response.Output.Write(sw.ToString());
        Response.Flush();
        Response.End();

    }

I tried this way also.....but not working...Please give a fix

 string tmpChartName = "test.png";
        string imgPath = HttpContext.Current.Request.PhysicalApplicationPath + tmpChartName;

        Chart1.SaveImage(imgPath);

        string imgPath2 = Request.Url.GetLeftPart(UriPartial.Authority) + VirtualPathUtility.ToAbsolute("~/" + tmpChartName);

        Response.Clear();
        Response.Buffer = true;
        Response.AddHeader("content-disposition", "attachment;filename=GridViewExport.xls");
        Response.Charset = "";

        Response.ContentType = "application/vnd.ms-excel";

        StringWriter stringWrite = new StringWriter();
        HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);
       // Chart1.RenderControl(htmlWrite);
        string headerTable = @"<Table><tr><td><img src='" + imgPath2 + @"' \></td></tr></Table>";

        Response.Write(headerTable);
        Response.Output.Write(stringWrite.ToString());
        Response.Flush();
        Response.End()