DataTable导入Excel

public void CreateExcel(System.Data.DataTable dt, string typeid, string FileName)
        {

            HttpResponse resp;

            resp = Page.Response;

            resp.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");

            resp.ContentType = "application/ms-excel";

            resp.AddHeader("Content-Disposition",

    "attachment; filename=" + System.Web.HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8) + ".xls");

            this.EnableViewState = false;

            string colHeaders = "", Is_item = "";

            int i = 0;

            //定义表对象与行对象，同时使用DataSet对其值进行初始化

            DataRow[] myRow = dt.Select("");

            //typeid=="1"时导出为Excel格式文件;typeid=="2"时导出为XML文件

            if (typeid == "1")
            {

                //取得数据表各列标题，标题之间以/t分割，最后一个列标题后加回车符

                for (i = 0; i < dt.Columns.Count; i++)
                {

                    colHeaders += dt.Columns[i].Caption.ToString() + "/t";

                }

                colHeaders += "/n";

                resp.Write(colHeaders);

                //逐行处理数据

                foreach (DataRow row in myRow)
                {

                    //在当前行中，逐列取得数据，数据之间以/t分割，结束时加回车符/n

                    for (i = 0; i < dt.Columns.Count; i++)
                    {

                        Is_item += row[i].ToString() + "/t";

                    }

                    Is_item += "/n";

                    resp.Write(Is_item);

                    Is_item = "";

                }

            }

            else
            {

                if (typeid == "2")
                {

                    //从DataSet中直接导出XML数据并且写到HTTP输出流中

                    resp.Write(dt.DataSet.GetXml());

                }

            }

            //写缓冲区中的数据到HTTP头文件中

            resp.End();

        }