freeCodeCamp/guide/chinese/javascript/standard-objects/object/object-isfrozen/index.md

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