JS 判断数组的五种方法

JS 判断数组的五种方法

1. Array.isArray()

let arr = []
console.log(Array.isArray(arr)) // true

2. instanceof

let arr = []
console.log(arr instanceof Array) // true

3. Object.prototype.toString.call()

let arr = []
console.log(Object.prototype.toString.call(arr) === '[object Array]') // true

4. constructor

let arr = []
console.log(arr.constructor === Array) // true

5. __ proto__

let arr = []
console.log(arr.__proto__ === Array.prototype) // true