区分数组和对象```js ``` let arr = [1,2] let bar = {name: '小白'} // /

    <script>
        let arr = [1,2]
        let bar = {name: '小白'}
        // // Array.isArray() 来判断
        console.log(Array.isArray(arr));
        console.log(Array.isArray(bar));

        // instanceof Array 来判断
        console.log(arr instanceof Array);
        console.log(bar instanceof Array);

        // constructor 判断
        console.log(arr.constructor); // Array() { [native code] }
        console.log(bar.constructor); // Object() { [native code] }

        // Object.prototype.toString.call() 判断
        console.log(Object.prototype.toString.call(arr)); // [object Array]
        console.log(Object.prototype.toString.call(bar)); // [object Object]
    </script>