freeCodeCamp/guide/chinese/javascript/standard-objects/number/number-isinteger/index.md

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---
title: Number isInteger
localeTitle: Number isInteger
---
# Number isInteger
## 描述
`Number.isInteger()`方法确定传递的值是否为整数。这种方法是在ES6中引入的
## 句法
`Number.isInteger(val)`
### 参数
**val** - 要检查是否为整数的值
## 返回值
一个[布尔值,](https://guide.freecodecamp.org/javascript/booleans)指示值是否为整数。
## 描述
如果传递的值是整数,则该方法返回`true` ,否则返回`false` 。无限和`NaN`值返回`false` 。
## 例子
```
Number.isInteger(0); // true
Number.isInteger(-0); // true
Number.isInteger(1); // true
Number.isInteger(2); // true
Number.isInteger(-100001); // true
Number.isInteger(999999999999999999999999); // true
Number.isInteger(0.1); // false
Number.isInteger(0.3); // false
Number.isInteger(Math.PI); // false
Number.isInteger(NaN); // false
Number.isInteger(Infinity); // false
Number.isInteger(-Infinity); // false
Number.isInteger('10'); // false
Number.isInteger(true); // false
Number.isInteger(false); // false
Number.isInteger([1]); // false
```
#### 更多信息:
[ECMA 2015文件](https://www.ecma-international.org/ecma-262/6.0/#sec-number.isinteger) [Number.isIntegerMDN Web文档](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isInteger)