Yii源码阅读笔记（九）

 1 namespace yii\base;
 2 
 3 /**
 4  * Behavior is the base class for all behavior classes.
 5  * 所有行为的基类
 6  * A behavior can be used to enhance the functionality of an existing component without modifying its code.
 7  * In particular, it can "inject" its own methods and properties into the component
 8  * and make them directly accessible via the component. It can also respond to the events triggered in the component
 9  * and thus intercept the normal code execution.
10  *
11  * @author Qiang Xue <qiang.xue@gmail.com>
12  * @since 2.0
13  */
14 class Behavior extends Object
15 {
16     /**
17      * @var 行为的依附对象
18      */
19     public $owner;
20 
21 
22     /**
23      * Declares event handlers for the [[owner]]‘s events.
24      * 表示这个行为将对类的何种事件进行何种反馈即可
25      *
26      * Child classes may override this method to declare what PHP callbacks should
27      * be attached to the events of the [[owner]] component.
28      *
29      * The callbacks will be attached to the [[owner]]‘s events when the behavior is
30      * attached to the owner; and they will be detached from the events when
31      * the behavior is detached from the component.
32      *
33      * The callbacks can be any of the following:
34      * 事件handler可以是以下形式：
35      *
36      * - method in this behavior: `‘handleClick‘`, equivalent to `[$this, ‘handleClick‘]`
37      *  字符串，表示行为类的方法，和事件不同，事件总的字符串形式表示全局函数，这里表示当前行为类的方法
38      * - object method: `[$object, ‘handleClick‘]`
39      *  一个对象或类的成员函数，以数组的形式
40      * - static method: `[‘Page‘, ‘handleClick‘]`
41      * - anonymous function: `function ($event) { ... }`
42      * 一个匿名函数
43      *
44      * The following is an example:
45      *
46      * ```php
47      * [
48      *     Model::EVENT_BEFORE_VALIDATE => ‘myBeforeValidate‘,
49      *     Model::EVENT_AFTER_VALIDATE => ‘myAfterValidate‘,
50      * ]
51      * ```
52      *
53      * @return 行为所有要响应的事件.
54      */
55     public function events()
56     {
57         return [];
58     }
59 
60     /**
61      * Attaches the behavior object to the component.
62      * 绑定行为到组件
63      * The default implementation will set the [[owner]] property
64      * and attach event handlers as declared in [[events]].
65      * 该方法会默认设置[[owner]]属性，且添加事件处理程序绑定到组件
66      * Make sure you call the parent implementation if you override this method.
67      * @param Component $owner the component that this behavior is to be attached to.
68      */
69     public function attach($owner)
70     {
71         $this->owner = $owner;//设置行为的 $owner ，使得行为可以访问、操作所依附的对象
72         foreach ($this->events() as $event => $handler) {//遍历行为中的 events() 返回的数组
73             //将准备响应的事件，通过所依附类的 on() 绑定到类上
74             $owner->on($event, is_string($handler) ? [$this, $handler] : $handler);//这里判断了事件是否是字符串的形式，如果是字符串，表示当前行为类的方法，用$this对象的形式添加
75         }
76     }
77 
78     /**
79      * Detaches the behavior object from the component.
80      * 解除行为的绑定
81      * The default implementation will unset the [[owner]] property
82      * 默认将 owner 属性设置为 null ，且解除绑定到类的处理程序
83      * and detach event handlers declared in [[events]].
84      * 
85      * Make sure you call the parent implementation if you override this method.
86      */
87     public function detach()
88     {
89         if ($this->owner) {
90             foreach ($this->events() as $event => $handler) {//遍历行为中的 events() 返回的数组
91                 //通过Component的 off() 将绑定到类上的事件hanlder解除下来
92                 $this->owner->off($event, is_string($handler) ? [$this, $handler] : $handler);
93             }
94             $this->owner = null;//将 $owner 设置为 null ，表示这个行为没有依附到任何类上
95         }
96     }
97 }

 1 namespace yii\base;
 2 
 3 use Yii;
 4 
 5 /**
 6  * Request represents a request that is handled by an [[Application]].
 7  *
 8  * @property boolean $isConsoleRequest The value indicating whether the current request is made via console.
 9  * @property string $scriptFile Entry script file path (processed w/ realpath()).
10  *
11  * @author Qiang Xue <qiang.xue@gmail.com>
12  * @since 2.0
13  */
14 abstract class Request extends Component
15 {
16     // 属性scriptFile，用于表示入口脚本
17     private $_scriptFile;
18     // 属性isConsoleRequest，用于表示是否是命令行应用
19     private $_isConsoleRequest;
20 
21 
22     /**
23      * Resolves the current request into a route and the associated parameters.
24      * 抽象函数，要求子类来实现 这个函数的功能主要是为了把Request解析成路由和相应的参数
25      * @return array the first element is the route, and the second is the associated parameters.
26      */
27     abstract public function resolve();
28 
29     /**
30      * Returns a value indicating whether the current request is made via command line
31      * isConsoleRequest属性的getter函数   使用 PHP_SAPI 常量判断当前应用是否是命令行应用
32      * @return boolean the value indicating whether the current request is made via console
33      */
34     public function getIsConsoleRequest()
35     {
36         // PHP_SAPI --判断解析php服务是由那种服务器软件，是采用那种协议
37         return $this->_isConsoleRequest !== null ? $this->_isConsoleRequest : PHP_SAPI === ‘cli‘;
38     }
39 
40     /**
41      * Sets the value indicating whether the current request is made via command line
42      * isConsoleRequest属性的setter函数 用来设置是否是命令行应用
43      * @param boolean $value the value indicating whether the current request is made via command line
44      */
45     public function setIsConsoleRequest($value)
46     {
47         $this->_isConsoleRequest = $value;
48     }
49 
50     /**
51      * Returns entry script file path.
52      * scriptFile属性的getter函数     通过 $_SERVER[‘SCRIPT_FILENAME‘] 来获取入口脚本名
53      * @return string entry script file path (processed w/ realpath())
54      * @throws InvalidConfigException if the entry script file path cannot be determined automatically.
55      */
56     public function getScriptFile()
57     {
58         if ($this->_scriptFile === null) {
59             if (isset($_SERVER[‘SCRIPT_FILENAME‘])) {
60                 $this->setScriptFile($_SERVER[‘SCRIPT_FILENAME‘]);
61             } else {
62                 throw new InvalidConfigException(‘Unable to determine the entry script file path.‘);
63             }
64         }
65 
66         return $this->_scriptFile;
67     }
68 
69     /**
70      * Sets the entry script file path.
71      * scriptFile属性的setter函数，用于设置入口脚本
72      * The entry script file path can normally be determined based on the `SCRIPT_FILENAME` SERVER variable.
73      * However, for some server configurations, this may not be correct or feasible.
74      * This setter is provided so that the entry script file path can be manually specified.
75      * @param string $value the entry script file path. This can be either a file path or a path alias.
76      * @throws InvalidConfigException if the provided entry script file path is invalid.
77      */
78     public function setScriptFile($value)
79     {
80         $scriptFile = realpath(Yii::getAlias($value));
81         if ($scriptFile !== false && is_file($scriptFile)) {
82             $this->_scriptFile = $scriptFile;
83         } else {
84             throw new InvalidConfigException(‘Unable to determine the entry script file path.‘);
85         }
86     }
87 }