Yii2的深入学习-yiibaseObject 类
Yii2的深入学习--yii\base\Object 类
之前我们说过 Yii2 中大多数类都继承自 yii\base\Object，今天就让我们来看一下这个类。
Object 是一个基础类，实现了属性的功能，其基本内容如下：
<span style="color: #000000;">phpnamespace yii\base;</span><span style="color: #0000ff;">use</span><span style="color: #000000;"> Yii;</span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Object 是一个基础类，实现了属性的功能 * Yii最基础的类，大多数类都继承了该类 </span><span style="color: #008000;">*/</span><span style="color: #0000ff;">class</span> <span style="color: #0000ff;">Object</span> <span style="color: #0000ff;">implements</span><span style="color: #000000;"> Configurable{ </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 获取静态方法调用的类名。返回类的名称，如果不是在类中调用则返回 FALSE。 </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">static</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> className() { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Constructor. </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> __construct(<span style="color: #800080;">$config</span> =<span style="color: #000000;"> []) { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 初始化对象 </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> init() { } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 魔术方法，实现 getter </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> __get(<span style="color: #800080;">$name</span><span style="color: #000000;">) { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 魔术方法，实现 setter </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> __set(<span style="color: #800080;">$name</span>, <span style="color: #800080;">$value</span><span style="color: #000000;">) { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 魔术方法，实现 isset，基于 getter 实现，有 getter 方法的属性才算存在 </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> __isset(<span style="color: #800080;">$name</span><span style="color: #000000;">) { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 魔术方法，实现 unset，基于 setter 实现，有 setter 方法的属性才能 unset 掉 </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> __unset(<span style="color: #800080;">$name</span><span style="color: #000000;">) { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Calls the named method which is not a class method. </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> __call(<span style="color: #800080;">$name</span>, <span style="color: #800080;">$params</span><span style="color: #000000;">) { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 检查对象或类是否具有 $name 属性，如果 $checkVars 为 true，则不局限于是否有 getter/setter </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> hasProperty(<span style="color: #800080;">$name</span>, <span style="color: #800080;">$checkVars</span> = <span style="color: #0000ff;">true</span><span style="color: #000000;">) { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 检查对象或类是否能够获取 $name 属性，如果 $checkVars 为 true，则不局限于是否有 getter </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> canGetProperty(<span style="color: #800080;">$name</span>, <span style="color: #800080;">$checkVars</span> = <span style="color: #0000ff;">true</span><span style="color: #000000;">) { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 检查对象或类是否能够设置 $name 属性，如果 $checkVars 为 true，则不局限于是否有 setter </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> canSetProperty(<span style="color: #800080;">$name</span>, <span style="color: #800080;">$checkVars</span> = <span style="color: #0000ff;">true</span><span style="color: #000000;">) { </span>...<span style="color: #000000;"> } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * 检查对象或类是否具有 $name 方法 </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> hasMethod(<span style="color: #800080;">$name</span><span style="color: #000000;">) { </span>...<span style="color: #000000;"> }}</span>如果想看详细的注释的话，可以访问 https://github.com/ReadCode/yii2-2.0.3-annotated/blob/master/framework/base/Object.php
从上面的内容中，我们可以看到 Object 类重写了 __get 和 __set 方法，下面我们来详细看下这两个方法：
<span style="color: #008000;">/*</span><span style="color: #008000;">* * Returns the value of an object property. * * Do not call this method directly as it is a PHP magic method that * will be implicitly called when executing `$value = $object->property;`. * * 魔术方法，实现 getter * * @param string $name the property name * @return mixed the property value * @throws UnknownPropertyException if the property is not defined * @throws InvalidCallException if the property is write-only * @see __set() </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> __get(<span style="color: #800080;">$name</span><span style="color: #000000;">) { </span><span style="color: #800080;">$getter</span> = 'get' . <span style="color: #800080;">$name</span><span style="color: #000000;">; </span><span style="color: #0000ff;">if</span> (<span style="color: #008080;">method_exists</span>(<span style="color: #800080;">$this</span>, <span style="color: #800080;">$getter</span><span style="color: #000000;">)) { </span><span style="color: #008000;">//</span><span style="color: #008000;"> 对象存在 $getter 方法，就直接调用</span> <span style="color: #0000ff;">return</span> <span style="color: #800080;">$this</span>-><span style="color: #800080;">$getter</span><span style="color: #000000;">(); } </span><span style="color: #0000ff;">elseif</span> (<span style="color: #008080;">method_exists</span>(<span style="color: #800080;">$this</span>, 'set' . <span style="color: #800080;">$name</span><span style="color: #000000;">)) { </span><span style="color: #008000;">//</span><span style="color: #008000;"> 如果存在 'set' . $name 方法，就认为该属性是只写的</span> <span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> InvalidCallException('Getting write-only property: ' . <span style="color: #008080;">get_class</span>(<span style="color: #800080;">$this</span>) . '::' . <span style="color: #800080;">$name</span><span style="color: #000000;">); } </span><span style="color: #0000ff;">else</span><span style="color: #000000;"> { </span><span style="color: #008000;">//</span><span style="color: #008000;"> 否则认为该属性不存在</span> <span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> UnknownPropertyException('Getting unknown property: ' . <span style="color: #008080;">get_class</span>(<span style="color: #800080;">$this</span>) . '::' . <span style="color: #800080;">$name</span><span style="color: #000000;">); } } </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Sets value of an object property. * * Do not call this method directly as it is a PHP magic method that * will be implicitly called when executing `$object->property = $value;`. * * 魔术方法，实现 setter * * @param string $name the property name or the event name * @param mixed $value the property value * @throws UnknownPropertyException if the property is not defined * @throws InvalidCallException if the property is read-only * @see __get() </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> __set(<span style="color: #800080;">$name</span>, <span style="color: #800080;">$value</span><span style="color: #000000;">) { </span><span style="color: #800080;">$setter</span> = 'set' . <span style="color: #800080;">$name</span><span style="color: #000000;">; </span><span style="color: #0000ff;">if</span> (<span style="color: #008080;">method_exists</span>(<span style="color: #800080;">$this</span>, <span style="color: #800080;">$setter</span><span style="color: #000000;">)) { </span><span style="color: #008000;">//</span><span style="color: #008000;"> 对象存在 $setter 方法，就直接调用</span> <span style="color: #800080;">$this</span>-><span style="color: #800080;">$setter</span>(<span style="color: #800080;">$value</span><span style="color: #000000;">); } </span><span style="color: #0000ff;">elseif</span> (<span style="color: #008080;">method_exists</span>(<span style="color: #800080;">$this</span>, 'get' . <span style="color: #800080;">$name</span><span style="color: #000000;">)) { </span><span style="color: #008000;">//</span><span style="color: #008000;"> 如果存在 'get' . $name 方法，就认为该属性是只读的</span> <span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> InvalidCallException('Setting read-only property: ' . <span style="color: #008080;">get_class</span>(<span style="color: #800080;">$this</span>) . '::' . <span style="color: #800080;">$name</span><span style="color: #000000;">); } </span><span style="color: #0000ff;">else</span><span style="color: #000000;"> { </span><span style="color: #008000;">//</span><span style="color: #008000;"> 否则认为该属性不存在</span> <span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> UnknownPropertyException('Setting unknown property: ' . <span style="color: #008080;">get_class</span>(<span style="color: #800080;">$this</span>) . '::' . <span style="color: #800080;">$name</span><span style="color: #000000;">); } }</span>基于上面的代码，我们可以看到，如果访问一个 Object 对象的某个属性， Yii会调用名为 get属性名() 的函数。如， SomeObject->Foo ， 会自动调用 SomeObject->getFoo()。 如果修改某一属性，会调用相应的setter函数。 如， SomeObject->Foo = $someValue ，会自动调用 SomeObject->setFoo($someValue) 。
以 SomeObject 的 Foo 为例，如果只存在 getFoo() 方法，那它就是只读的，如果只存在 setFoo() 方法，那它就是只写的，只有两个方法都存在的时候才是既可读又可写的。
需要注意的一点是只有在读取和写入对象的一个不存在的成员变量时， __get() __set() 会被自动调用。 如果 Foo 是一个 public 的属性就不会经过 __get() 和 __set() 方法了。
所以通常属性是 private 的，举个例子如下：
<span style="color: #0000ff;">class</span> User <span style="color: #0000ff;">extends</span> yii\base\<span style="color: #0000ff;">Object</span><span style="color: #000000;">{ </span><span style="color: #0000ff;">private</span> <span style="color: #800080;">$_name</span><span style="color: #000000;">; </span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> getName() { </span><span style="color: #0000ff;">return</span> <span style="color: #800080;">$this</span>-><span style="color: #000000;">_name; } </span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> setName(<span style="color: #800080;">$name</span><span style="color: #000000;">) { </span><span style="color: #800080;">$this</span>->_name = <span style="color: #008080;">trim</span>(<span style="color: #800080;">$name</span><span style="color: #000000;">); }}</span>我们还可以在 get 和 set 方法中做一些特殊的处理。
除了 __get() __set() 之外， yii\base\Object 还提供了以下方法便于使用属性：
- __isset() 用于测试属性值是否不为 null ，在 isset($object->property) 时被自动调用。 注意该属性要有相应的 getter。
- __unset() 用于将属性值设为 null ，在 unset($object->property) 时被自动调用。 注意该属性要有相应的 setter。
- hasProperty() 用于测试是否有某个属性。即，定义了 getter 或 setter。 如果 hasProperty() 的参数 $checkVars = true （默认为true）， 那么只要具有同名的成员变量也认为具有该属性，如前面提到的 public $title 。
- canGetProperty() 测试一个属性是否可读，参数 $checkVars 的意义同上。只要定义了 getter，属性即可读。 同时，如果 $checkVars 为 true 。那么只要类定义了成员变量，不管是 public， private 还是 protected， 都认为是可读。
- canSetProperty() 测试一个属性是否可写，参数 $checkVars 的意义同上。只要定义了 setter，属性即可写。 同时，在 $checkVars 为 ture 。那么只要类定义了成员变量，不管是 public， private 还是 protected， 都认为是可写。
对 Yii2 源码有兴趣的同学可以关注项目 yii2-2.0.3-annotated，现在在上面已经添加了不少关于 Yii2 源码的注释，之后还会继续添加～
有兴趣的同学也可以参与进来，提交 Yii2 源码的注释。
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
Solution: Your organization requires you to change your PIN
Oct 04, 2023 pm 05:45 PM
The message "Your organization has asked you to change your PIN" will appear on the login screen. This happens when the PIN expiration limit is reached on a computer using organization-based account settings, where they have control over personal devices. However, if you set up Windows using a personal account, the error message should ideally not appear. Although this is not always the case. Most users who encounter errors report using their personal accounts. Why does my organization ask me to change my PIN on Windows 11? It's possible that your account is associated with an organization, and your primary approach should be to verify this. Contacting your domain administrator can help! Additionally, misconfigured local policy settings or incorrect registry keys can cause errors. Right now
How to adjust window border settings on Windows 11: Change color and size
Sep 22, 2023 am 11:37 AM
Windows 11 brings fresh and elegant design to the forefront; the modern interface allows you to personalize and change the finest details, such as window borders. In this guide, we'll discuss step-by-step instructions to help you create an environment that reflects your style in the Windows operating system. How to change window border settings? Press + to open the Settings app. WindowsI go to Personalization and click Color Settings. Color Change Window Borders Settings Window 11" Width="643" Height="500" > Find the Show accent color on title bar and window borders option, and toggle the switch next to it. To display accent colors on the Start menu and taskbar To display the theme color on the Start menu and taskbar, turn on Show theme on the Start menu and taskbar
How to change title bar color on Windows 11?
Sep 14, 2023 pm 03:33 PM
By default, the title bar color on Windows 11 depends on the dark/light theme you choose. However, you can change it to any color you want. In this guide, we'll discuss step-by-step instructions for three ways to change it and personalize your desktop experience to make it visually appealing. Is it possible to change the title bar color of active and inactive windows? Yes, you can change the title bar color of active windows using the Settings app, or you can change the title bar color of inactive windows using Registry Editor. To learn these steps, go to the next section. How to change title bar color in Windows 11? 1. Using the Settings app press + to open the settings window. WindowsI go to "Personalization" and then
OOBELANGUAGE Error Problems in Windows 11/10 Repair
Jul 16, 2023 pm 03:29 PM
Do you see "A problem occurred" along with the "OOBELANGUAGE" statement on the Windows Installer page? The installation of Windows sometimes stops due to such errors. OOBE means out-of-the-box experience. As the error message indicates, this is an issue related to OOBE language selection. There is nothing to worry about, you can solve this problem with nifty registry editing from the OOBE screen itself. Quick Fix – 1. Click the “Retry” button at the bottom of the OOBE app. This will continue the process without further hiccups. 2. Use the power button to force shut down the system. After the system restarts, OOBE should continue. 3. Disconnect the system from the Internet. Complete all aspects of OOBE in offline mode
How to enable or disable taskbar thumbnail previews on Windows 11
Sep 15, 2023 pm 03:57 PM
Taskbar thumbnails can be fun, but they can also be distracting or annoying. Considering how often you hover over this area, you may have inadvertently closed important windows a few times. Another disadvantage is that it uses more system resources, so if you've been looking for a way to be more resource efficient, we'll show you how to disable it. However, if your hardware specs can handle it and you like the preview, you can enable it. How to enable taskbar thumbnail preview in Windows 11? 1. Using the Settings app tap the key and click Settings. Windows click System and select About. Click Advanced system settings. Navigate to the Advanced tab and select Settings under Performance. Select "Visual Effects"
Display scaling guide on Windows 11
Sep 19, 2023 pm 06:45 PM
We all have different preferences when it comes to display scaling on Windows 11. Some people like big icons, some like small icons. However, we all agree that having the right scaling is important. Poor font scaling or over-scaling of images can be a real productivity killer when working, so you need to know how to customize it to get the most out of your system's capabilities. Advantages of Custom Zoom: This is a useful feature for people who have difficulty reading text on the screen. It helps you see more on the screen at one time. You can create custom extension profiles that apply only to certain monitors and applications. Can help improve the performance of low-end hardware. It gives you more control over what's on your screen. How to use Windows 11
10 Ways to Adjust Brightness on Windows 11
Dec 18, 2023 pm 02:21 PM
Screen brightness is an integral part of using modern computing devices, especially when you look at the screen for long periods of time. It helps you reduce eye strain, improve legibility, and view content easily and efficiently. However, depending on your settings, it can sometimes be difficult to manage brightness, especially on Windows 11 with the new UI changes. If you're having trouble adjusting brightness, here are all the ways to manage brightness on Windows 11. How to Change Brightness on Windows 11 [10 Ways Explained] Single monitor users can use the following methods to adjust brightness on Windows 11. This includes desktop systems using a single monitor as well as laptops. let's start. Method 1: Use the Action Center The Action Center is accessible
How to turn off private browsing authentication for iPhone in Safari?
Nov 29, 2023 pm 11:21 PM
In iOS 17, Apple introduced several new privacy and security features to its mobile operating system, one of which is the ability to require two-step authentication for private browsing tabs in Safari. Here's how it works and how to turn it off. On an iPhone or iPad running iOS 17 or iPadOS 17, Apple's browser now requires Face ID/Touch ID authentication or a passcode if you have any Private Browsing tab open in Safari and then exit the session or app to access them again. In other words, if someone gets their hands on your iPhone or iPad while it's unlocked, they still won't be able to view your privacy without knowing your passcode
