private void export_to_word()
    {

        try
        {
            data_grid_print.Visible = true;
            //grd_detail.Visible = true;
            Response.Clear();
            Response.AddHeader("content-disposition", "attachment;filename=FileName.doc");
            Response.Charset = "";
            Response.Cache.SetCacheability(HttpCacheability.NoCache);
            Response.ContentType = "application/vnd.word";

            System.IO.StringWriter stringWrite = new System.IO.StringWriter();
            System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);

            data_grid_print.RenderControl(htmlWrite);
            Response.Write(stringWrite.ToString());

            Response.End();
            htmlWrite.Flush();
            //grd_detail.Visible = false;
            data_grid_print.Visible = false;
        }
        catch (Exception ex)
        {
        }
    }