public FileResult ExportExcel()

        {

            var sbHtml = new StringBuilder();

            sbHtml.Append("<table border='1' cellspacing='0' cellpadding='0'>");

            sbHtml.Append("<tr>");

            var lstTitle = new List<string> { "编号", "姓名", "年龄", "创建时间" };

            foreach (var item in lstTitle)

            {

                sbHtml.AppendFormat("<td style='font-size: 14px;text-align:center;background-color: #DCE0E2; font-weight:bold;' height='25'>{0}</td>", item);

            }

            sbHtml.Append("</tr>");

            for (int i = ; i < ; i++)

            {

                sbHtml.Append("<tr>");

                sbHtml.AppendFormat("<td style='font-size: 12px;height:20px;'>{0}</td>", i);

                sbHtml.AppendFormat("<td style='font-size: 12px;height:20px;'>屌丝{0}号</td>", i);

                sbHtml.AppendFormat("<td style='font-size: 12px;height:20px;'>{0}</td>", new Random().Next(, ) + i);

                sbHtml.AppendFormat("<td style='font-size: 12px;height:20px;'>{0}</td>", DateTime.Now);

                sbHtml.Append("</tr>");

            }

            sbHtml.Append("</table>");

            //第一种:使用FileContentResult

            byte[] fileContents = Encoding.Default.GetBytes(sbHtml.ToString());

            return File(fileContents, "application/ms-excel", "fileContents.xls");

            //第二种:使用FileStreamResult

            var fileStream = new MemoryStream(fileContents);

            return File(fileStream, "application/ms-excel", "fileStream.xls");

            //第三种:使用FilePathResult

            //服务器上首先必须要有这个Excel文件,然会通过Server.MapPath获取路径返回.

            var fileName = Server.MapPath("~/Files/fileName.xls");

            return File(fileName, "application/ms-excel", "fileName.xls");

        }