thinkphp自动创建数据对象解析

   public function create($data=‘‘,$type=‘‘) {
      // 如果没有传值默认取POST数据
      if(empty($data)) {
          $data   =   I(‘post.‘);
      }elseif(is_object($data)){
          $data   =   get_object_vars($data);
      }
      // 判断是否有主键，有代表修改，没有代表插入
      $type = $type?:(!empty($data[$this->getPk()])?self::MODEL_UPDATE:self::MODEL_INSERT);


      // 生成数据对象，先获取该模型所有的字段$fields，过滤掉$data中不在field数据中的字段（最后剩下表中存在的字段）
      if($this->autoCheckFields) { // 开启字段检测 则过滤非法字段数据
          $fields =   $this->getDbFields();
          foreach ($data as $key=>$val){
              if(!in_array($key,$fields)) {
                  unset($data[$key]);
              }elseif(MAGIC_QUOTES_GPC && is_string($val)){
                  $data[$key] =   stripslashes($val);
              }
          }
      }

      $this->data =   $data;
      return $data;
   }

  /**
   * 获取数据表字段信息
   * @access public
   * @return array
   */
  public function getDbFields(){
      if(isset($this->options[‘table‘])) {// 动态指定表名
          $array      =   explode(‘ ‘,$this->options[‘table‘]);
          $fields     =   $this->db->getFields($array[0]);
          return  $fields?array_keys($fields):false;
      }
      if($this->fields) {
          $fields     =  $this->fields;
          unset($fields[‘_type‘],$fields[‘_pk‘]);
          return $fields;
      }
      return false;
  }

  public function getFields($tableName) {
      $result =   $this->query(‘SHOW COLUMNS FROM ‘.$this->parseKey($tableName));
      $info   =   array();
      if($result) {
          foreach ($result as $key => $val) {
              $info[$val[‘Field‘]] = array(
                  ‘name‘    => $val[‘Field‘],
                  ‘type‘    => $val[‘Type‘],
                  ‘notnull‘ => (bool) (strtoupper($val[‘Null‘]) === ‘NO‘), // not null is empty, null is yes
                  ‘default‘ => $val[‘Default‘],
                  ‘primary‘ => (strtolower($val[‘Key‘]) == ‘pri‘),
                  ‘autoinc‘ => (strtolower($val[‘Extra‘]) == ‘auto_increment‘),
              );
          }
      }
      return $info;
  }