yii2框架随笔5

/**
     * Returns a value indicating whether a property is defined for this component.
     * A property is defined if:
     *
     * - the class has a getter or setter method associated with the specified name
     *   (in this case, property name is case-insensitive);
     * - the class has a member variable with the specified name (when `$checkVars` is true);
     * - an attached behavior has a property of the given name (when `$checkBehaviors` is true).
     *
     * 与 Object 中的方法类似，只是添加了是否检测 behavior 的参数(下一篇着重介绍Object.php类)
     *
     * @param string $name the property name
     * @param boolean $checkVars whether to treat member variables as properties
     * @param boolean $checkBehaviors whether to treat behaviors‘ properties as properties of this component
     * @return boolean whether the property is defined
     * @see canGetProperty()
     * @see canSetProperty()
     */
    public function hasProperty($name, $checkVars = true, $checkBehaviors = true)
    {
        // $checkVars 标记是否 check 对象的是否具有该属性（不是 getter 和 setter 定义出的属性）
        // $checkBehaviors 标记是否 check behavior 中的属性
        return $this->canGetProperty($name, $checkVars, $checkBehaviors) || $this->canSetProperty($name, false, $checkBehaviors);
    }
    /**
     * Returns a value indicating whether a property can be read.
     * A property can be read if:
     *
     * - the class has a getter method associated with the specified name
     *   (in this case, property name is case-insensitive);
     * - the class has a member variable with the specified name (when `$checkVars` is true);
     * - an attached behavior has a readable property of the given name (when `$checkBehaviors` is true).
     *
     * 检查对象或类是否能够获取 $name 属性
     *
     * @param string $name the property name
     * @param boolean $checkVars whether to treat member variables as properties
     * @param boolean $checkBehaviors whether to treat behaviors‘ properties as properties of this component
     * @return boolean whether the property can be read
     * @see canSetProperty()
     */
    public function canGetProperty($name, $checkVars = true, $checkBehaviors = true)
    {
        if (method_exists($this, ‘get‘ . $name) || $checkVars && property_exists($this, $name)) {
            return true;
        } elseif ($checkBehaviors) {
            $this->ensureBehaviors();
            foreach ($this->_behaviors as $behavior) {
                if ($behavior->canGetProperty($name, $checkVars)) {
                    // behavior 中存在名为 $name 的可读属性，就认为该对象也存在
                    return true;
                }
            }
        }
        return false;
    }
    /**
     * Returns a value indicating whether a property can be set.
     * A property can be written if:
     *
     * - the class has a setter method associated with the specified name
     *   (in this case, property name is case-insensitive);
     * - the class has a member variable with the specified name (when `$checkVars` is true);
     * - an attached behavior has a writable property of the given name (when `$checkBehaviors` is true).
     *
     * 检查对象或类是否能够设置 $name 属性
     *
     * @param string $name the property name
     * @param boolean $checkVars whether to treat member variables as properties
     * @param boolean $checkBehaviors whether to treat behaviors‘ properties as properties of this component
     * @return boolean whether the property can be written
     * @see canGetProperty()
     */
    public function canSetProperty($name, $checkVars = true, $checkBehaviors = true)
    {
        if (method_exists($this, ‘set‘ . $name) || $checkVars && property_exists($this, $name)) {
            return true;
        } elseif ($checkBehaviors) {
            $this->ensureBehaviors();
            foreach ($this->_behaviors as $behavior) {
                if ($behavior->canSetProperty($name, $checkVars)) {
                    // behavior 中存在名为 $name 的可写属性，就认为该对象也存在
                    return true;
                }
            }
        }
        return false;
    }
    /**
     * Returns a value indicating whether a method is defined.
     * A method is defined if:
     *
     * - the class has a method with the specified name
     * - an attached behavior has a method with the given name (when `$checkBehaviors` is true).
     *
     * 检查对象或类是否具有 $name 方法, $checkBehaviors 标记是否 check behavior 中的方法
     *
     * @param string $name the property name
     * @param boolean $checkBehaviors whether to treat behaviors‘ methods as methods of this component
     * @return boolean whether the property is defined
     */
    public function hasMethod($name, $checkBehaviors = true)
    {
        if (method_exists($this, $name)) {
            return true;
        } elseif ($checkBehaviors) {
            $this->ensureBehaviors();
            foreach ($this->_behaviors as $behavior) {
                if ($behavior->hasMethod($name)) {
                    // behavior 中存在名为 $name 的方法，就认为该对象也存在
                    return true;
                }
            }
        }
        return false;
    }

/**
     * Returns a list of behaviors that this component should behave as.
     *
     * Child classes may override this method to specify the behaviors they want to behave as.
     *
     * The return value of this method should be an array of behavior objects or configurations
     * indexed by behavior names. A behavior configuration can be either a string specifying
     * the behavior class or an array of the following structure:
     *
     * ~~~
     * ‘behaviorName‘ => [
     *     ‘class‘ => ‘BehaviorClass‘,
     *     ‘property1‘ => ‘value1‘,
     *     ‘property2‘ => ‘value2‘,
     * ]
     * ~~~
     *
     * Note that a behavior class must extend from [[Behavior]]. Behavior names can be strings
     * or integers. If the former, they uniquely identify the behaviors. If the latter, the corresponding
     * behaviors are anonymous and their properties and methods will NOT be made available via the component
     * (however, the behaviors can still respond to the component‘s events).
     *
     * Behaviors declared in this method will be attached to the component automatically (on demand).
     *
     * 定义该对象中要用到的 behavior，格式如上
     *
     * @return array the behavior configurations.
     */
    public function behaviors()
    {
        return [];//返回一个空数组
    }

因为此类继承了Object,下一篇我们着重分析一下Object.php这个类。