forEach和ES6实现tab切换

  <ul class="nav">
        <!-- <li>
            <a href="">前端</a>
            <ul class="select">
                <li>就业班</li>
                <li>精品</li>
                <li>学院福利</li>
            </ul>
        </li>
        <li>
            <a href="">Python</a>

        </li>
        <li>
            <a href="">JavaEE</a>

        </li> -->
    </ul>

        * {
            margin: 0;
            padding: 0;
        }
        
        a {
            color: black;
            text-decoration: none;
        }
        
        li {
            width: 70px;
            list-style: none;
        }
        
        .nav {
            text-decoration: none;
            list-style: none;
        }
        
        .nav>li {
            background-color: lightsteelblue;
            padding: 10px 15px;
            text-align: center;
            float: left;
        }

 <script src="../阶段四jquery/jquery编程/jquery.min.js"></script>
     <script>
        var arr1 = ['前端', 'Python', 'JavaEE'];
        var arr2 = ['就业班', '精品', '学院福利'];
        var nava = ``;
        var naul = ``;
        arr1.forEach(function(item) {
            console.log(item);
            nava += `<li><a href="">${item}</a><ul class=" rel="external nofollow" select"></ul></li> `;
            $(".nav").html(nava);

        });

        arr2.forEach(function(item) {
            console.log(item);
            naul += `<li>${item}</li>`;
            $(".select").html(naul);
        });


        $(".nav>li").children("ul").hide();


        $(".nav>li").mouseleave(function() {
            $(this).children("ul").hide();
        });

        $(".nav>li").mouseover(function() {
            $(this).children("ul").show();

        });
    </script>