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我在做gridview导出excel，我是引用别人的方法，别人的都正常，我下载后的就是乱码，可穿进去的时候显示是正常的，请问应该在哪儿修改一下呢？ /// <summary>
        /// 导出成Excel
        /// </summary>
        /// <param name="page">要导出的页面.如:this.Page</param>
        /// <param name="tab">包含数据的DataTable</param>
        /// <param name="FileName">要保存的文件名,如test.xls</param>
        public static void Export(System.Web.UI.Page page, System.Data.DataTable tab, string FileName)
        {
            System.Web.HttpResponse httpResponse = page.Response;
            System.Web.UI.WebControls.DataGrid dataGrid = new System.Web.UI.WebControls.DataGrid();
            dataGrid.DataSource = tab.DefaultView;
            dataGrid.AllowPaging = false;
            dataGrid.HeaderStyle.BackColor = System.Drawing.Color.Transparent;
            dataGrid.HeaderStyle.HorizontalAlign = HorizontalAlign.Center;
            dataGrid.HeaderStyle.Font.Bold = true;
            dataGrid.DataBind();
            httpResponse.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8)); //filename="*.xls";
            httpResponse.ContentEncoding = System.Text.Encoding.GetEncoding("UTF-8") ;
            httpResponse.ContentType = "application/ms-excel";
            System.IO.StringWriter tw = new System.IO.StringWriter();
            System.Web.UI.HtmlTextWriter hw = new System.Web.UI.HtmlTextWriter(tw);
            dataGrid.RenderControl(hw);            string filePath = page.Server.MapPath("..") + "\\" + FileName;
            System.IO.StreamWriter sw = System.IO.File.CreateText(filePath);
            sw.Write(tw.ToString());
            sw.Close();            DownFile(httpResponse, FileName, filePath);            httpResponse.End();
        }private static bool DownFile(System.Web.HttpResponse Response, string fileName, string fullPath)
        {
            try
            {
                Response.ContentType = "application/octet-stream";                Response.AppendHeader("Content-Disposition", "attachment;filename=" +
                 HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8) + ";charset=GB2312");
                System.IO.FileStream fs = System.IO.File.OpenRead(fullPath);
                long fLen = fs.Length;
                int size = 102400;//每100K同时下载数据 
                byte[] readData = new byte[size];//指定缓冲区的大小 
                if (size > fLen) size = Convert.ToInt32(fLen);
                long fPos = 0;
                bool isEnd = false;
                while (!isEnd)
                {
                    if ((fPos + size) > fLen)
                    {
                        size = Convert.ToInt32(fLen - fPos);
                        readData = new byte[size];
                        isEnd = true;
                    }
                    fs.Read(readData, 0, size);//读入一个压缩块 
                    Response.BinaryWrite(readData);
                    fPos += size;
                }
                fs.Close();
                System.IO.File.Delete(fullPath);
                return true;
            }
            catch
            {
                return false;
            }
        }