.net 手动导出excel

private StringWriter GetStringWriter(DataTable dt)

    {

        StringWriter sw = new StringWriter();

        //读列名   

        foreach (DataColumn dc in dt.Columns)

            sw.Write(dc.ColumnName + "\t");



        //读列值   

        //重新的一行   

        sw.Write(sw.NewLine);

        if (dt != null)

        {

            foreach (DataRow dr in dt.Rows)

            {

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

                {

                    sw.Write(dr[i].ToString() + "\t");

                }

                sw.Write(sw.NewLine);

            }

        }

        sw.Close();



        return sw;

    }



    protected void ExcelImport(DataTable dt, string ExportFileName)

    {

        StringWriter sw = GetStringWriter(dt);

        //当前编码   

        HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");

        //把输出的文件名进行编码   

        string fileName = HttpUtility.UrlEncode(ExportFileName, System.Text.Encoding.UTF8);

        //文件名   

        string str = "attachment;filename=" + fileName + ".xls";

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

        //把文件头输出，此文件头激活文件下载框   

        HttpContext.Current.Response.AppendHeader("Content-Disposition", str);//http报头文件   

        HttpContext.Current.Response.ContentType = "application/ms-excel";

        this.Page.EnableViewState = false;



        Response.Write(sw);

        Response.End();

    }