js 验证对象是否为数组

<script>
    /**
     *
     * @param obj 传入需要验证的对象
     * @returns {boolean}
     */
    function isArray(obj) {
        return Object.prototype.toString.call(obj) == "[object Array]";
    }
</script>

 /*数字索引的数组*/
    var arr =[1,2,3];
    console.log(typeof arr);//object
    console.log(isArray(arr));//true

    /*非数字索引的数组*/
    var newArr = [];
    newArr[‘a‘] = "sss";
    newArr[‘b‘] = 88;

    console.log(typeof newArr);//object
    console.log(isArray(newArr));//true

    /*非数组的对象*/
    var dateObj = new Date();

    console.log(typeof dateObj);//object
    console.log(isArray(dateObj));//false