JS 判断数组的五种方法
- Array.isArray()
let arr = []
console.log(Array.isArray(arr)) // true
- instanceof
let arr = []
console.log(arr instanceof Array) // true
- Object.prototype.toString.call()
let arr = []
console.log(Object.prototype.toString.call(arr) === '[object Array]') // true
- constructor
let arr = []
console.log(arr.constructor === Array) // true
- __ proto__
let arr = []
console.log(arr.__proto__ === Array.prototype) // true