39 lines
949 B
Markdown
39 lines
949 B
Markdown
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---
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title: Object isFrozen
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localeTitle: 对象是冷冻
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---
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## 对象是冷冻
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您可以使用**`Object.isFrozen()`**来确定对象是否已冻结。它返回**`true`**或**`false`**布尔值。
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#### **句法**
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```javascript
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Object.isFrozen(obj)
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```
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**例如：**
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```javascript
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var foods = {
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grain : "wheat",
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dairy : "milk",
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vegetable : "carrot",
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fruit : "grape"
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};
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var frozenFoods = Object.freeze(foods);
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var areMyFoodsFrozen = Object.isFrozen(frozenFoods);
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\\ returns true
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```
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请记住，冻结的对象**不能**更改其属性。
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如果您尝试在非对象参数上使用**`Object.isFrozen()`** ，它将返回`true` 。
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#### 更多信息：
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[MDN Object.isFrozen（）](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/isFrozen)
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[MDN Object.freeze（）](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/freeze)
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