原文地址:http://www.it610.com/article/4918541.htm
行为就是继承yii\base\behavior,可以绑定到任意yii\base\compent实例上,然后这个compent实例就拥有了行为类所具有的属性和方法;
注意:Behavior只能与Component类绑定
参考出处:http://www.digpage.com/behavior.html
下面是两个例子:
1、分别定义行为类MyBehavior.php和组件类MyBehaviorAttachClass.php
(1)MyBehavior.php
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | <? php namespace app\models; use yii\base\Behavior; ?> <? class MyBehavior extends Behavior { public $ propertyTest = 'this is MyBehavior propertyTest' ; public function methodTest() { echo 'this is MyBehavior methodTest'; } } ?> |
(2)MyBehaviorAttachClass.php
1 2 3 4 5 6 7 8 9 10 | <? php namespace app\models; use yii\base\component; ?> <? class MyBehaviorAttachClass extends component { } ?> |
(3)控制器中写个方法,以便演示时调用
1 2 3 4 5 6 7 8 | public function actionBehavior() { $MyBehavior=new MyBehavior; $MyBehaviorAttachClass=new MyBehaviorAttachClass; $MyBehaviorAttachClass->attachBehavior('MyBehavior',$MyBehavior); echo $MyBehaviorAttachClass->propertyTest; echo $MyBehaviorAttachClass->methodTest(); } |
此时运行r=hello/Behavior就会显示如下界面:
2、在ActiveRecord中调用行为,这种属于静态调用,直接在类中写个behaviors方法就可以了
详情看:http://www.yiichina.com/question/807
下面是gii_test.php,位于models下
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 | class gii_test extends \yii\db\ActiveRecord { public function behaviors() { return [ [ 'class' => TimestampBehavior::className(), 'attributes' => [ ActiveRecord::EVENT_BEFORE_INSERT => ['created_at'],//其中created_at和updated_at是gii_test数据表的字段名,必须设置为int才能显示时间戳 ActiveRecord::EVENT_BEFORE_UPDATE => ['updated_at'],//否则显示00000000 ], ], ]; } } |
如果需要保留字段属性为 timestamp
,可以使用如下方法自动填充:
1 2 3 4 5 6 7 8 9 10 11 12 | use yii\db\Expression; public function behaviors() { return [ [ 'class' => TimestampBehavior::className(), 'createdAtAttribute' => 'created_at', 'updatedAtAttribute' => 'updated_at', 'value' => new Expression('NOW()'), ], ]; } |