PHP yii实现model添加默认值的方法(两种方法)

public function rules()
{
 // NOTE: you should only define rules for those attributes that
 // will receive user inputs.
 return array(
  array('start, end', 'required'),
  array('user_id', 'numerical', 'integerOnly'=>true),
  array('timestamp','default','value'=>date('Y-m-d H:i:s')),
  // The following rule is used by search().
  // Please remove those attributes that should not be searched.
  array('id, start, end, user_id, timestamp', 'safe', 'on'=>'search'),
 );
}

function beforeSave()
{
 $this->user_id = Yii::app()->user->id;
 return true;
}