68 lines
1.7 KiB
Markdown
68 lines
1.7 KiB
Markdown
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---
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title: Object Freeze
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localeTitle: 对象冻结
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---
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## 对象冻结
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`Object.freeze()`方法冻结了一个对象。冻结的对象会_阻止您_ ：
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* 添加新属性
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* 从中删除现有的特性
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* 更改其现有属性的可枚举性，可配置性或可写性
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### 句法
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```javascript
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Object.freeze(obj)
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```
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### 参数
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`obj`
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* 要冻结的对象。
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### 返回
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冻结的物体。
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### 重要的提示
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尝试添加，删除或修改冻结对象的属性将导致失败。此失败将是静默或抛出`TypeError` （如果启用了严格模式）。另外， `Object.freeze()`是一个浅操作。这意味着冻结对象的嵌套对象是可修改的。
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### 例
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```javascript
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// Create your object
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let person = {
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name: 'Johnny',
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age: 23,
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guild: 'Army of Darkness',
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hobbies: ['music', 'gaming', 'rock climbing']
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}
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// Modify your object
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person.name = 'John'
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person.age = 24
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person.hobbies.splice(1,1)
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delete person.guild
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// Verify your object has been modified
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console.log(person) // { name: 'John', age: 24, hobbies: ['music', 'rock climbing']
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// Freeze your object
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Object.freeze(person)
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// Verify that your object can no longer be modified
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person.name = 'Johnny' // fails silently
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person.age = 23 // fails silently
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console.log(person) // { name: 'John', age: 24, hobbies: ['music', 'rock climbing']
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// The freeze is "shallow" and nested objects (including arrays) can still be modified
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person.hobbies.push('basketball')
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consol.log(person.hobbies) // ['music', 'rock climbing', 'basketball']
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```
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#### 更多信息：
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[MDN文档](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/freeze)
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