请看代码演示
let arr = [123, 456, 789];
console.log(arr instanceof Array);
console.log(Array.isArray(arr));
console.log(arr.constructor === Array);
console.log(Object.prototype.toString.apply(arr) === "[object Array]");
console.log(Array.prototype.isPrototypeOf(arr));
console.log(Object.getPrototypeOf(arr) === Array.prototype)
