.net导出数据到Excel

    public class ExportHelper
    {

        //导出execl
        private void Export(string fileType, string fileName, GridView grd)
        {

            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.Charset = "GB2312";
            HttpContext.Current.Response.ContentEncoding = Encoding.UTF8;
            HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(fileName, Encoding.UTF8));
            HttpContext.Current.Response.ContentType = fileType;
            grd.EnableViewState = false;
            var tw = new StringWriter();
            var hw = new HtmlTextWriter(tw);
            DisableControls(grd);
            grd.RenderControl(hw);
            const string strStyle = "<style>.xlString { mso-number-format:\\@; } </style>";
            HttpContext.Current.Response.Write(strStyle);
            HttpContext.Current.Response.Write(tw.ToString());
            HttpContext.Current.Response.Write(strStyle);
            HttpContext.Current.Response.End();

        }

        //将button，linkbutton，dropdownlist 都转换成为文本
        private void DisableControls(Control gv)
        {
            var l = new Literal();
            for (int i = 0; i < gv.Controls.Count; i++)
            {
                Type type = gv.Controls[i].GetType();
                if (type == typeof(LinkButton))
                {
                    l.Text = ((LinkButton)gv.Controls[i]).Text;
                    gv.Controls.Remove(gv.Controls[i]);
                    gv.Controls.AddAt(i, l);
                }
                else if (type == typeof(DropDownList))
                {
                    l.Text = ((DropDownList)gv.Controls[i]).SelectedItem.Text;
                    gv.Controls.Remove(gv.Controls[i]);
                    gv.Controls.AddAt(i, l);
                }
                else if (type == typeof(Button))
                {
                    l.Text = ((Button)gv.Controls[i]).Text;
                    gv.Controls.Remove(gv.Controls[i]);
                    gv.Controls.AddAt(i, l);
                }
                if (gv.Controls[i].HasControls())
                {
                    DisableControls(gv.Controls[i]);
                }
            }
        }

    }