[JavaScript知识库]js数组去重

    function Unique(arr) {
        var ary = [];
        for (var i = 0; i < arr.length; i++) {
            // ary.indexOf(arr[i])查找数组中重复元素首次出现的下标，没有返回-1
            if (ary.indexOf(arr[i]) == -1) {
                ary.push(arr[i]);
            } else {
                console.log('重复元素下标：' + ary.indexOf(arr[i]))
            }
        }
        return ary;
    }
    console.log(Unique([1, 31, 13, 4, 5, 'a', 1, 'd', 'a', 31]));