upload控件上传json文件合并的两种方法

 byte[] byte1 = FileUpload1.FileBytes;
            byte[] byte2 = FileUpload2.FileBytes;
            byte[] a1 = Encoding.UTF8.GetBytes("[");
            byte[] a2 = Encoding.UTF8.GetBytes(",");
            byte[] a3 = Encoding.UTF8.GetBytes("]");
            byte[] totalaa = new byte[a1.Length + byte1.Length + a2.Length + byte2.Length + a3.Length];
            a1.CopyTo(totalaa, 0);
            byte1.CopyTo(totalaa, a1.Length);
            a2.CopyTo(totalaa, a1.Length + byte1.Length);
            byte2.CopyTo(totalaa, a1.Length + byte1.Length + a2.Length);
            a3.CopyTo(totalaa, a1.Length + byte1.Length + a2.Length + byte2.Length);
            string total1 = Encoding.UTF8.GetString(totalaa);

            string fileName = Path.GetFileNameWithoutExtension(FileUpload1.PostedFile.FileName); //获取文件名（不包括扩展名）
            string Extension1 = Path.GetExtension(FileUpload1.PostedFile.FileName);//扩展名
            string Extension2 = Path.GetExtension(FileUpload2.PostedFile.FileName);
            if (Extension1 == "" || Extension2 == "")
            {

                Response.Write("<script>alert(‘请添加文件‘);</script>");
                return;

            }
            if (FileUpload1.PostedFile.FileName == FileUpload2.PostedFile.FileName)
            {

                Response.Write("<script>alert(‘请添加不同的文件‘);</script>");
                return;

            }
            if (Extension1.ToLower() != ".txt" || Extension2.ToLower() != ".txt")
            {

                Response.Write("<script>alert(‘文件后缀名不正确！请输入txt的文件‘);</script>");
                return;

            }
            if (Directory.Exists(Server.MapPath("~/UploadFile")) == false)//判断文件夹是否存在,若不存在则创建
            {
                Directory.CreateDirectory(Server.MapPath("~/UploadFile"));
            }
            string UploadFilePath = Server.MapPath("UploadFile\\");
            string fullName = FileUpload1.PostedFile.FileName;
            string newName = DateTime.Now.ToString("yyyyddmmhhss") + fullName.Substring(fullName.LastIndexOf("."));
            FileUpload1.SaveAs(UploadFilePath + FileUpload1.PostedFile.FileName);
            FileUpload2.SaveAs(UploadFilePath + FileUpload2.PostedFile.FileName);
            FileStream fs = new FileStream(UploadFilePath + newName, FileMode.Create);
            string line1 = string.Empty;
            string line2 = string.Empty;
            using (StreamReader sr1 = new StreamReader(UploadFilePath + FileUpload1.PostedFile.FileName))
            {
                line1 = sr1.ReadToEnd();
            }
            using (StreamReader sr2 = new StreamReader(UploadFilePath + FileUpload2.PostedFile.FileName))
            {
                line2 = sr2.ReadToEnd();
            }
            try
            {
                string total = "[" + line1 + "," + line2 + "]";
                StreamWriter sw = new StreamWriter(fs);
                sw.Write(total);
                sw.Flush();
                sw.Close();
                fs.Close();
                if (File.Exists(UploadFilePath + FileUpload1.PostedFile.FileName))
                {
                    File.Delete(UploadFilePath + FileUpload1.PostedFile.FileName);
                }
                if (File.Exists(UploadFilePath + FileUpload2.PostedFile.FileName))
                {
                    File.Delete(UploadFilePath + FileUpload2.PostedFile.FileName);
                }
                showmessage.InnerText = "文件上传成功！";
            }
            catch
            {
                showmessage.InnerText = "文件上传失败！";
            }