继续了解controller基类。
<span>/*</span><span>*
* Runs a request specified in terms of a route.在路径中指定的请求。
* The route can be either an ID of an action within this controller or a complete route consisting
* of module IDs, controller ID and action ID. If the route starts with a slash '/', the parsing of
* the route will start from the application; otherwise, it will start from the parent module of this controller.
* 该路径可以是控制器内的一个动作的标识，或由模块标识、控制器标识和动作标识组成的一个完整路径。
* 如果该路径从一个“/”开始，该路径的解析将从应用程序开始；否则，它将从该控制器的父模块开始。
* @param string $route the route to be handled, e.g., 'view', 'comment/view', '/admin/comment/view'.
* @param array $params the parameters to be passed to the action.
* @return mixed the result of the action.
* @see runAction()
</span><span>*/</span>
<span>public</span> function run($route, $<span>params</span> =<span> [])
{
$pos </span>= strpos($route, <span>'</span><span>/</span><span>'</span><span>);
</span><span>if</span> ($pos === <span>false</span>) {<span>//</span><span>判断是否以“/”开始 是则解析从应用程序开始；否则，它将从该控制器的父模块开始。</span>
<span>return</span> $<span>this</span>->runAction($route, $<span>params</span><span>);
} elseif ($pos </span>> <span>0</span><span>) {
</span><span>return</span> $<span>this</span>->module->runAction($route, $<span>params</span><span>);
} </span><span>else</span><span> {
</span><span>return</span> Yii::$app->runAction(ltrim($route, <span>'</span><span>/</span><span>'</span>), $<span>params</span><span>);
}
}
</span><span>/*</span><span>*
* Binds the parameters to the action.将参数绑定到动作标识。
* This method is invoked by [[Action]] when it begins to run with the given parameters.
* 运行给定的参数时，该方法被调用。
* @param Action $action the action to be bound with parameters.参数约束的操作。
* @param array $params the parameters to be bound to the action.要约束的参数。
* @return array the valid parameters that the action can run with.可以运行的有效参数。
</span><span>*/</span>
<span>public</span> function bindActionParams($action, $<span>params</span><span>)
{
</span><span>return</span><span> [];
}
</span><span>/*</span><span>*
* Creates an action based on the given action ID. 根据给定的操作标识创建一个action。
* The method first checks if the action ID has been declared in [[actions()]]. If so,
* it will use the configuration declared there to create the action object.
* If not, it will look for a controller method whose name is in the format of `actionXyz`
* where `Xyz` stands for the action ID. If found, an [[InlineAction]] representing that
* method will be created and returned.
* 该方法首先检查动作标识是否在 [[actions()]]设置，如果是将使用配置声明来创建操作对象。
* 如果不是，它会寻找控制器方法`Xyz` 的 `actionXyz`作为动作标识，调用[[InlineAction]]方法创建对象
* @param string $id the action ID.
* @return Action the newly created action instance. Null if the ID doesn't resolve into any action.
</span><span>*/</span>
<span>public</span><span> function createAction($id)
{
</span><span>if</span> ($id === <span>''</span><span>) {
</span><span>//</span><span> 如果action的id为空，就是用默认的action</span>
$id = $<span>this</span>-><span>defaultAction;
}
$actionMap </span>= $<span>this</span>->actions();<span>//</span><span> 获取actions方法中的定义的actionMap</span>
<span>if</span><span> (isset($actionMap[$id])) {
</span><span>//</span><span> 如果操作标识在actionMap中，就去创建这个action</span>
<span>return</span> Yii::createObject($actionMap[$id], [$id, $<span>this</span><span>]);
} elseif (preg_match(</span><span>'</span><span>/^[a-z0-9\\-_]+$/</span><span>'</span>, $id) && strpos($id, <span>'</span><span>--</span><span>'</span>) === <span>false</span> && trim($id, <span>'</span><span>-</span><span>'</span>) ===<span> $id) {
</span><span>//</span><span> 如果id符合命名规范，而且两边不存在-
</span><span>//</span><span> 用于拼接controller类名类似的方法拼接action方法的名称</span>
$methodName = <span>'</span><span>action</span><span>'</span> . str_replace(<span>'</span> <span>'</span>, <span>''</span>, ucwords(implode(<span>'</span> <span>'</span>, explode(<span>'</span><span>-</span><span>'</span><span>, $id))));
</span><span>if</span> (method_exists($<span>this</span><span>, $methodName)) {
</span><span>//</span><span> 如果方法存在，就实例化</span>
$method = <span>new</span> \ReflectionMethod($<span>this</span><span>, $methodName);
</span><span>if</span> ($method->isPublic() && $method->getName() ===<span> $methodName) {
</span><span>//</span><span> 如果方法是public的，就new一个InlineAction返回</span>
<span>return</span> <span>new</span> InlineAction($id, $<span>this</span><span>, $methodName);
}
}
}
</span><span>return</span> <span>null</span><span>;
}
</span><span>/*</span><span>*
* This method is invoked right before an action is executed.
* 在执行操作之前调用此方法。
* The method will trigger the [[EVENT_BEFORE_ACTION]] event. The return value of the method
* will determine whether the action should continue to run.
* 方法将触发 [[EVENT_BEFORE_ACTION]] 事件，返回值确定该操作是否执行
* If you override this method, your code should look like the following:
*
* ```php
* public function beforeAction($action)
* {
* if (parent::beforeAction($action)) {
* // your custom code here
* return true; // or false if needed
* } else {
* return false;
* }
* }
* ```
*
* @param Action $action the action to be executed. 执行的操作
* @return boolean whether the action should continue to run.确定操作是否应该继续运行。
</span><span>*/</span>
<span>public</span><span> function beforeAction($action)
{
$</span><span>event</span> = <span>new</span><span> ActionEvent($action);
$</span><span>this</span>->trigger(self::EVENT_BEFORE_ACTION, $<span>event</span><span>);
</span><span>return</span> $<span>event</span>-><span>isValid;
}
</span><span>/*</span><span>*
* This method is invoked right after an action is executed.
* 在执行操作之后调用此方法。
* The method will trigger the [[EVENT_AFTER_ACTION]] event. The return value of the method
* will be used as the action return value.
*
* If you override this method, your code should look like the following:
*
* ```php
* public function afterAction($action, $result)
* {
* $result = parent::afterAction($action, $result);
* // your custom code here
* return $result;
* }
* ```
*
* @param Action $action the action just executed. 刚刚执行的操作。
* @param mixed $result the action return result. 操作返回值
* @return mixed the processed action result. 处理结果。
</span><span>*/</span>
<span>public</span><span> function afterAction($action, $result)
{
$</span><span>event</span> = <span>new</span><span> ActionEvent($action);
$</span><span>event</span>->result =<span> $result;
$</span><span>this</span>->trigger(self::EVENT_AFTER_ACTION, $<span>event</span><span>);
</span><span>return</span> $<span>event</span>-><span>result;
}
</span><span>/*</span><span>*
* Returns all ancestor modules of this controller. 获取当前控制器所有的父模块
* The first module in the array is the outermost one (i.e., the application instance),
* while the last is the innermost one.
* 数组中的第一个模块是最外层的一个，最后一个模块是最内层的。
* @return Module[] all ancestor modules that this controller is located within.当前控制器所有的父模块
</span><span>*/</span>
<span>public</span><span> function getModules()
{
</span><span>//</span><span> 当前controller的module组成的数组</span>
$modules = [$<span>this</span>-><span>module];
$module </span>= $<span>this</span>-><span>module;
</span><span>while</span> ($module->module !== <span>null</span><span>) {
</span><span>//</span><span> 将外面的module插入到modules数组的开头</span>
array_unshift($modules, $module-><span>module);
$module </span>= $module-><span>module;
}
</span><span>return</span><span> $modules;
}
</span><span>/*</span><span>*
* @return string the controller ID that is prefixed with the module ID (if any).
* 返回控制器id
</span><span>*/</span>
<span>public</span><span> function getUniqueId()
{
</span><span>//</span><span>如果当前所属模块为application，则就为当前id,否则要面要加上模块id</span>
<span>return</span> $<span>this</span>->module instanceof Application ? $<span>this</span>->id : $<span>this</span>->module->getUniqueId() . <span>'</span><span>/</span><span>'</span> . $<span>this</span>-><span>id;
}
</span><span>/*</span><span>*
* Returns the route of the current request. 获取默认请求的路由信息
* @return string the route (module ID, controller ID and action ID) of the current request.
* 当前请求的路由（模块标识、控制器标识和操作标识）
</span><span>*/</span>
<span>public</span><span> function getRoute()
{
</span><span>return</span> $<span>this</span>->action !== <span>null</span> ? $<span>this</span>->action->getUniqueId() : $<span>this</span>-><span>getUniqueId();
}
</span><span>/*</span><span>*
* Renders a view and applies layout if available.
* 如果有布局渲染视图文件和布局文件
* The view to be rendered can be specified in one of the following formats:
*
* - path alias (e.g. "@app/views/site/index");
* - absolute path within application (e.g. "//site/index"): the view name starts with double slashes.
* The actual view file will be looked for under the [[Application::viewPath|view path]] of the application.
* - absolute path within module (e.g. "/site/index"): the view name starts with a single slash.
* The actual view file will be looked for under the [[Module::viewPath|view path]] of [[module]].
* - relative path (e.g. "index"): the actual view file will be looked for under [[viewPath]].
*
* To determine which layout should be applied, the following two steps are conducted:
* 确定应用布局文件类型的步骤：
* 1. In the first step, it determines the layout name and the context module:
* 首先确定布局文件名和背景模块
* - If [[layout]] is specified as a string, use it as the layout name and [[module]] as the context module;
* - If [[layout]] is null, search through all ancestor modules of this controller and find the first
* module whose [[Module::layout|layout]] is not null. The layout and the corresponding module
* are used as the layout name and the context module, respectively. If such a module is not found
* or the corresponding layout is not a string, it will return false, meaning no applicable layout.
* 如果布局文件是字符串，也就是设置布局文件，则直接调用。 如果没有设置布局文件，则查找所有的父模块的布局文件。
* 2. In the second step, it determines the actual layout file according to the previously found layout name
* and context module. The layout name can be:
* 应用下的布局文件，以“/”开头，这个会从应用程序的布局文件目录下面查找布局文件
* - a path alias (e.g. "@app/views/layouts/main");
* - an absolute path (e.g. "/main"): the layout name starts with a slash. The actual layout file will be
* looked for under the [[Application::layoutPath|layout path]] of the application;
* - a relative path (e.g. "main"): the actual layout file will be looked for under the
* [[Module::layoutPath|layout path]] of the context module.
*
* If the layout name does not contain a file extension, it will use the default one `.php`.
* 如果布局文件没有扩展名，则默认为.php
* @param string $view the view name.
* @param array $params the parameters (name-value pairs) that should be made available in the view.
* These parameters will not be available in the layout.
* @return string the rendering result.
* @throws InvalidParamException if the view file or the layout file does not exist.
</span><span>*/</span>
<span>public</span> function render($view, $<span>params</span> =<span> [])
{
</span><span>//</span><span>由view对象渲染视图文件</span>
$content = $<span>this</span>->getView()->render($view, $<span>params</span>, $<span>this</span><span>);
</span><span>return</span> $<span>this</span>->renderContent($content);<span>//</span><span>渲染布局文件</span>
<span> }
</span><span>/*</span><span>*
* Renders a static string by applying a layout. 配合render方法渲染布局文件
* @param string $content the static string being rendered 被渲染的静态字符串
* @return string the rendering result of the layout with the given static string as the `$content` variable.
* If the layout is disabled, the string will be returned back.
* 以给定的静态字符串作为“$content”变量布局的渲染结果。如果布局被禁用，将返回该字符串。
* @since 2.0.1
</span><span>*/</span>
<span>public</span><span> function renderContent($content)
{
$layoutFile </span>= $<span>this</span>->findLayoutFile($<span>this</span>->getView()); <span>//</span><span>查找布局文件</span>
<span>if</span> ($layoutFile !== <span>false</span>) {<span>//</span><span>由view对象渲染布局文件，并把上视图结果作为content变量传递到布局中，</span>
<span>return</span> $<span>this</span>->getView()->renderFile($layoutFile, [<span>'</span><span>content</span><span>'</span> => $content], $<span>this</span><span>);
} </span><span>else</span><span> {
</span><span>return</span><span> $content;
}
}
</span><span>/*</span><span>*
* Renders a view without applying layout.渲染视图文件不应用布局
* This method differs from [[render()]] in that it does not apply any layout.
* 这种方法不同于[[render()]]，它不使用任何布局。
* @param string $view the view name. Please refer to [[render()]] on how to specify a view name.
* 视图名称。根据[[render()]]指定一个视图名称。
* @param array $params the parameters (name-value pairs) that should be made available in the view.
* 在视图中提供的参数(name-value pairs)
* @return string the rendering result.渲染结果。
* @throws InvalidParamException if the view file does not exist.如果视图文件不存在，抛出异常
</span><span>*/</span>
<span>public</span> function renderPartial($view, $<span>params</span> =<span> [])
{
</span><span>return</span> $<span>this</span>->getView()->render($view, $<span>params</span>, $<span>this</span><span>);
}
</span><span>/*</span><span>*
* Renders a view file. 渲染一个文件
* @param string $file the view file to be rendered. This can be either a file path or a path alias.
* 要呈现的视图文件。可以是一个文件路径或路径别名。
* @param array $params the parameters (name-value pairs) that should be made available in the view.
* 在视图中提供的参数(name-value pairs)
* @return string the rendering result.渲染结果
* @throws InvalidParamException if the view file does not exist.如果视图文件不存在，抛出异常
</span><span>*/</span>
<span>public</span> function renderFile($file, $<span>params</span> =<span> [])
{
</span><span>return</span> $<span>this</span>->getView()->renderFile($file, $<span>params</span>, $<span>this</span><span>);
}
</span><span>/*</span><span>*
* Returns the view object that can be used to render views or view files.
* 返回渲染视图或视图文件的view对象。
* The [[render()]], [[renderPartial()]] and [[renderFile()]] methods will use
* this view object to implement the actual view rendering.
* [[render()]], [[renderPartial()]] and [[renderFile()]] 方法将使用视图对象实现视图显示。
* If not set, it will default to the "view" application component.如果未设置，则默认为“view”应用程序组件。
* @return View|\yii\web\View the view object that can be used to render views or view files.
* 渲染视图或视图文件的view对象。
</span><span>*/</span>
<span>public</span><span> function getView()
{
</span><span>if</span> ($<span>this</span>->_view === <span>null</span><span>) {
$</span><span>this</span>->_view = Yii::$app-><span>getView();
}
</span><span>return</span> $<span>this</span>-><span>_view;
}
</span><span>/*</span><span>*
* Sets the view object to be used by this controller.
* @param View|\yii\web\View $view the view object that can be used to render views or view files.
</span><span>*/</span>
<span>public</span><span> function setView($view)
{
$</span><span>this</span>->_view =<span> $view;
}
</span><span>/*</span><span>*
* Returns the directory containing view files for this controller.返回该控制器包含视图文件的目录。
* The default implementation returns the directory named as controller [[id]] under the [[module]]'s
* [[viewPath]] directory.默认返回目录命名为控制器[[id]] 下的 [[module]]的[[viewPath]]目录。
* @return string the directory containing the view files for this controller.
* 包含此控制器的视图文件的目录。
</span><span>*/</span>
<span>public</span><span> function getViewPath()
{
</span><span>return</span> $<span>this</span>->module->getViewPath() . DIRECTORY_SEPARATOR . $<span>this</span>-><span>id;
}
</span><span>/*</span><span>*
* Finds the applicable layout file.查找适用的布局文件。
* @param View $view the view object to render the layout file.呈现布局文件视图对象。
* @return string|boolean the layout file path, or false if layout is not needed.
* Please refer to [[render()]] on how to specify this parameter.
* 布局文件路径，或者不需要布局。参阅[[render()]]如何指定此参数。
* @throws InvalidParamException if an invalid path alias is used to specify the layout.
* 如果使用了无效的路径别名指定布局。抛出异常
</span><span>*/</span>
<span>public</span><span> function findLayoutFile($view)
{
$module </span>= $<span>this</span>-><span>module;
</span><span>if</span> (is_string($<span>this</span>-><span>layout)) {
</span><span>//</span><span>如果当前控制器设置了布局文件，则直接使用所设置的布局文件</span>
$layout = $<span>this</span>-><span>layout;
} elseif ($</span><span>this</span>->layout === <span>null</span><span>) {
</span><span>//</span><span>如果没有设置布局文件，查找所有的父模块的布局文件。</span>
<span>while</span> ($module !== <span>null</span> && $module->layout === <span>null</span><span>) {
$module </span>= $module-><span>module;
}
</span><span>if</span> ($module !== <span>null</span> && is_string($module-><span>layout)) {
$layout </span>= $module-><span>layout;
}
}
</span><span>if</span> (!<span>isset($layout)) {
</span><span>return</span> <span>false</span>;<span>//</span><span>如果没有设置布局文件，返回false</span>
<span> }
</span><span>if</span> (strncmp($layout, <span>'</span><span>@</span><span>'</span>, <span>1</span>) === <span>0</span><span>) {
$file </span>= Yii::getAlias($layout);<span>//</span><span>以“@”开头，会在别名路径中查找布局文件</span>
} elseif (strncmp($layout, <span>'</span><span>/</span><span>'</span>, <span>1</span>) === <span>0</span>) {<span>//</span><span>以“/”开头，会从应用程序的布局文件目录下面查找布局文件</span>
$file = Yii::$app->getLayoutPath() . DIRECTORY_SEPARATOR . substr($layout, <span>1</span><span>);
} </span><span>else</span> {<span>//</span><span>从当前模块的布局文件目录下查找布局文件</span>
$file = $module-><span>getLayoutPath() . DIRECTORY_SEPARATOR . $layout;
}
</span><span>if</span> (pathinfo($file, PATHINFO_EXTENSION) !== <span>''</span><span>) {
</span><span>return</span> $file;<span>//</span><span>如果布局文件有文件扩展名，返回文件</span>
<span> }
$path </span>= $file . <span>'</span><span>.</span><span>'</span> . $view->defaultExtension;<span>//</span><span>拼接默认的文件扩展名。</span>
<span>if</span> ($view->defaultExtension !== <span>'</span><span>php</span><span>'</span> && !<span>is_file($path)) {
$path </span>= $file . <span>'</span><span>.php</span><span>'</span>;<span>//</span><span>如果文件不存在，并且，默认的文件扩展名也不是php，则加上.php作为扩展名。</span>
<span> }
</span><span>return</span><span> $path;
}</span>
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