I Am Trying To Upload Multiple Files But Whenever I Convert Filesize Into Byte[] It Shows 0 .In Documnet Binary It Is Coming Zero Please Help Me?

if (gvAttachments.Rows.Count > 0)
          {
              string[] Records = Session["FileDetail"].ToString().Split('#');
              for (int i = 0; i < Records.Length; i++)
              {
                  string[] arrRecords = Records[i].Split(',');
                  string[] fileExtension = arrRecords[0].Split('.');
                  string documentType = string.Empty;
                  switch (fileExtension[1])
                  {
                      case "pdf": documentType = "application/pdf";
                          break;
                      case "xls": documentType = "application/vnd.ms-excel";
                          break;
                      case "xlsx": documentType = "application/vnd.ms-excel";
                          break;
                      case "doc": documentType = "application/vnd.ms-word";
                          break;
                      case "docx": documentType = "application/vnd.ms-word";
                          break;
                      case "gif": documentType = "image/gif";
                          break;
                      case "png": documentType = "image/png";
                          break;
                      case "jpg": documentType = "image/jpg";
                          break;
                  }
                  string size = arrRecords[2];
                  int fileSize = Convert.ToInt32(size);
                  byte[] documentbinary = new byte[fileSize];
                  fuUpload.PostedFile.InputStream.Read(documentbinary, 0, fileSize);
                  string file = arrRecords[0].ToString();
                  string format = documentType.ToString();
                  cmd = new SqlCommand();
                  cmd.CommandText = "Insert into Attachment(File_Name,File_Format,File_Content,User_Notice_Mapping_ID) values('" + file + "','" + format + "',@DocData," + userNoticeID + ")";
                  cmd.CommandType = CommandType.Text;
                  cmd.Connection = con;
                  cmd.Parameters.Add("@DocData", SqlDbType.VarBinary, fileSize);
                  cmd.Parameters["@DocData"].Value = documentbinary;
                  cmd.ExecuteNonQuery();
                  String msg = "Your message has been Sent Successfully";
                  ShowAlert(msg, true);
              }
          }