Behvaior类

原文地址: http://www.cnblogs.com/dragon16/p/5532430.html

Behavior类是所有事件类的基类：

目录yii2\base\Behavior.php

<?php/** * @link http://www.yiiframework.com/ * @copyright Copyright (c) 2008 Yii Software LLC * @license http://www.yiiframework.com/license/ */namespace yii\base;/** * Behavior is the base class for all behavior classes. * 所有行为的基类 * A behavior can be used to enhance the functionality of an existing component without modifying its code. * In particular, it can "inject" its own methods and properties into the component * and make them directly accessible via the component. It can also respond to the events triggered in the component * and thus intercept the normal code execution. * 用来增强现有组件的功能而不修改它的代码。它可以添加自己的方法和属性组件 * 使他们可以直接通过组件访问。还可以响应组件触发的事件，拦截正常的代码执行。 * @author Qiang Xue <[e-mail]> * @since 2.0 * 继承父类Object */class Behavior extends Object{    /**     * @var Component the owner of this behavior 要附加行为对象的组件。     */    public $owner;    /**     * Declares event handlers for the [[owner]]'s events.     * 声明[[owner]]的事件处理程序     * Child classes may override this method to declare what PHP callbacks should     * be attached to the events of the [[owner]] component.     * 子类可以重写此方法 php回调应连接 [[owner]]组件。     * The callbacks will be attached to the [[owner]]'s events when the behavior is     * attached to the owner; and they will be detached from the events when     * the behavior is detached from the component.     * 当行为被连接到owner时回调将附在[[owner]]的事件中，当行为从组件中分离时，它们将被分离     * The callbacks can be any of the followings:     *     * - method in this behavior: `'handleClick'`, equivalent to `[$this, 'handleClick']`     * - object method: `[$object, 'handleClick']`     * - static method: `['Page', 'handleClick']`     * - anonymous function: `function ($event) { ... }`     *     * The following is an example:     *     * ~~~     * [     *     Model::EVENT_BEFORE_VALIDATE => 'myBeforeValidate',     *     Model::EVENT_AFTER_VALIDATE => 'myAfterValidate',     * ]     * ~~~     *     * @return array events (array keys) and the corresponding event handler methods (array values).     * 事件和相应的事件处理方法     */    public function events()    {        return [];    }    /**     * Attaches the behavior object to the component.绑定行为到组件     * The default implementation will set the [[owner]] property        * and attach event handlers as declared in [[events]].     * 默认设置[[owner]]属性并将事件处理程序绑定到组件     * Make sure you call the parent implementation if you override this method. 如果重写方法，确保调用父类去实现     * @param Component $owner the component that this behavior is to be attached to. 行为绑定到$owner组件     */    public function attach($owner)    {       $this->owner = $owner;//设置 $owner ，使得所依附的对象可以访问、操作        foreach ($this->events() as $event => $handler) {            //将准备响应的事件，通过所依附类的 on()方法 绑定到类上            $owner->on($event, is_string($handler) ? [$this, $handler] : $handler);        }    }    /**     * Detaches the behavior object from the component. 解除绑定的行为     * The default implementation will unset the [[owner]] property 默认取消 owner的属性     * and detach event handlers declared in [[events]].    将events中的事件程序解除绑定     * Make sure you call the parent implementation if you override this method.如果重写方法，确保调用父类去实现     */    public function detach()    {        if ($this->owner) {            foreach ($this->events() as $event => $handler) {//遍历行为中 events() 返回的数组                //通过Component的 off() 将绑定到类上的事件解除                $this->owner->off($event, is_string($handler) ? [$this, $handler] : $handler);            }            $this->owner = null;//将 $owner 设置为 null ，表示这个解除绑定        }    }}