/**
  * 删除字段
  * @param  int   $id 需要删除字段的id
  * @return array
  */
 public function delete($id)
 {
     if (!isset($id) || !$this->existField($id)) {
         return resultReturn(false);
     }
     $Field = $this->getD();
     $old = $Field->getById($id);
     $model = M('Model')->field('tbl_name')->getById($old['model_id']);
     $Field->startTrans();
     $status = $Field->where("id={$old['id']}")->delete();
     // 删除表中的字段
     $dcs = $Field->dropColumn($model['tbl_name'], $old['name']);
     if (false === $status || false === $dcs) {
         $Field->addColumn($model['tbl_name'], $old['name'], $old['type'], $old['length'], $old['value'], $old['comment']);
         $Field->rollback();
         return $this->resultReturn(false);
     }
     $Field->commit();
     return $this->resultReturn(true);
 }
 private function filterParam($userId, &$unick, $password, $rptpassword, $school, $email)
 {
     if (!isValidStringLength($userId, 3, 20)) {
         resultReturn(1002, array('msg' => '用户ID长度限制在3-20之间!'));
     }
     if (!isValidUserId($userId)) {
         resultReturn(1002, array('msg' => '用户ID只能包含数字和字母!'));
     }
     if (!isValidStringLength($unick, -1, 100)) {
         resultReturn(1002, array('msg' => '用户昵称长度不符合规范!'));
     }
     if (empty($unick)) {
         $unick = $userId;
     }
     if (strcmp($password, $rptpassword) != 0) {
         resultReturn(1002, array('msg' => '密码填写不一致!'));
     }
     if (!isValidStringLength($password, 6)) {
         resultReturn(1002, array('msg' => '密码长度至少6位!'));
     }
     if (!isValidStringLength($school, -1, 100)) {
         resultReturn(1002, array('msg' => '学校名称长度不符合规范!'));
     }
     if (!isValidStringLength($email, -1, 100)) {
         resultReturn(1002, array('msg' => '邮箱长度不符合规范!'));
     } else {
         if (!empty($email) && !isValidEmail($email)) {
             resultReturn(1002, array('msg' => '邮箱格式不符合规范!'));
         }
     }
 }