Action类

原文地址: http://www.cnblogs.com/dragon16/p/5543886.html

Action是所有控制器的基类

yii2\base\Action.php

<?php/** * @link http://www.yiiframework.com/ * @copyright Copyright (c) 2008 Yii Software LLC * @license http://www.yiiframework.com/license/ */namespace yii\base;use Yii;/** * Action is the base class for all controller action classes. * 是所有控制器的基类 * Action provides a way to divide a complex controller into * smaller actions in separate class files. * 控制器提供了一种重复使用操作方法的代码，在多个控制器或不同的项目中使用 * Derived classes must implement a method named `run()`. This method * will be invoked by the controller when the action is requested. * The `run()` method can have parameters which will be filled up * with user input values automatically according to their names. * 派生类必须实现一个名为run()的方法，这个方法会在控制器被请求时调用。 * 它可以有参数，将用户输入值的根据他们的名字自动填补。 * For example, if the `run()` method is declared as follows: * 例：run()方法调用声明如下： * ~~~ * public function run($id, $type = 'book') { ... } * ~~~ * * And the parameters provided for the action are: `['id' => 1]`. * Then the `run()` method will be invoked as `run(1)` automatically. * 并且提供了操作的参数 ['id'=>1]; * 当run(1)时自动调用run(); * @property string $uniqueId The unique ID of this action among the whole application. This property is * read-only. * 整个应用程序中，这一行动的唯一标识。此属性是只读 * @author Qiang Xue <[e-mail]> * @since 2.0 */class Action extends Component{    /**     * @var string ID of the action     ID的动作     */    public $id;    /**     * @var Controller|\yii\web\Controller the controller that owns this action     * 拥有这一行动的控制器     */    public $controller;    /**     * Constructor.     * 构造函数     * @param string $id the ID of this action  这一行动的ID     * @param Controller $controller the controller that owns this action 拥有这一行动的控制器     * @param array $config name-value pairs that will be used to initialize the object properties     * 用来初始化对象属性的 name-value      */    public function __construct($id, $controller, $config = [])    {        $this->id = $id;        $this->controller = $controller;        //调用父类的__construct()方法        parent::__construct($config);    }    /**     * Returns the unique ID of this action among the whole application.     * 返回整个应用程序中的唯一ID。     * @return string the unique ID of this action among the whole application.     * 在整个应用程序中，这一行动的唯一ID。     */    public function getUniqueId()    {        return $this->controller->getUniqueId() . '/' . $this->id;    }    /**     * Runs this action with the specified parameters.  用指定的参数运行此操作。     * This method is mainly invoked by the controller. 该方法主要由控制器调用。     *     * @param array $params the parameters to be bound to the action's run() method.绑定到行动的run()方法的参数。     * @return mixed the result of the action   行动的结果  命名参数是否有效的     * @throws InvalidConfigException if the action class does not have a run() method     * 如果动作类没有run()方法 扔出异常     */    public function runWithParams($params)    {        if (!method_exists($this, 'run')) {//如果动作类没有run()方法 抛出异常            throw new InvalidConfigException(get_class($this) . ' must define a "run()" method.');        }        //调用bindActionParams()方法将参数绑定到动作。        $args = $this->controller->bindActionParams($this, $params);        //记录跟踪消息        Yii::trace('Running action: ' . get_class($this) . '::run()', __METHOD__);        if (Yii::$app->requestedParams === null) {            //请求的动作提供的参数            Yii::$app->requestedParams = $args;        }        if ($this->beforeRun()) {            //执行run()方法            $result = call_user_func_array([$this, 'run'], $args);            $this->afterRun();            return $result;        } else {            return null;        }    }    /**     * This method is called right before `run()` is executed.     * ` run() `执行前方法被调用。     * You may override this method to do preparation work for the action run.     * 可以重写此方法，为该操作运行的准备工作。     * If the method returns false, it will cancel the action.     * 如果该方法返回false，取消该操作。     * @return boolean whether to run the action.     */    protected function beforeRun()    {        return true;    }    /**     * This method is called right after `run()` is executed.       ` run() `执行后 方法被调用。     * You may override this method to do post-processing work for the action run.     * 可以重写此方法来处理该动作的后续处理工作。     */    protected function afterRun()    {    }}