---
url: https://sugarat.top/interview/js/judgeArr.md
---

# 如何判断数组

## 1.Array.isArray

```js
console.log(Array.isArray([])) // true
```

## 2.instanceof

```js
console.log([] instanceof Array)
```

## 3.constructor

```js
function isArray(arr) {
    if (!(arr instanceof Object)) {
        return false
    }
    return arr.constructor === Array
}
console.log(isArray([]))
```

## 4.Object.prototype.toString

```js
function isArray(arr) {
    return Object.prototype.toString.call(arr) === '[object Array]'
}
console.log(isArray([]))
```

## 5.正则+JSON.stringify

```js
function isArray(arr) {
    try {
        return /^\[.*\]$/.test(JSON.stringify(arr))
    } catch (err) {
        return false
    }
}
console.log(isArray([]))
```