index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title> 封装一个 Tab 组件</title>
    <style>
        ul,li{
            margin:0;
            padding:0;
        }
        li{
            list-style: none;
        }
        .clearfix:after{
            content: '';
            display: block;
            clear: both;
        }
        .tab{
            width:600px;
            margin:20px auto;
            border:1px solid #ccc;
            padding: 20px 10px;
            border-radius: 4px;
        }
        .tab-header{
            border-bottom:1px solid #ccc ;

        }
        .tab-header>li{
            float: left;
            color: brown;
            border-top:1px solid #fff;
            border-left: 1px solid #fff;
            border-right: 1px solid #fff;
            padding: 10px 20px;
            cursor: pointer;
        }
        .tab-header .active{
            border:1px solid #ccc;
            border-bottom-color: #fff;
            border-radius: 4px 4px 0 0;
            color: #333;
            margin-bottom: -1px;
        }
        .tab-container{
            padding: 20px 10px;
        }
        .tab-container>li{
            display: none;
        }
        .tab-container>.active{
            display: block;
        }


    </style>
</head>
<body>
<div class="tab">
    <ul class="tab-header clearfix">
        <li class="active">选项1</li>
        <li>选项2</li>
        <li>选项3</li>
        <li>选项4</li>
    </ul>
    <ul class="tab-container">
        <li class="active">内容1</li>
        <li>内容2</li>
        <li>内容3</li>
        <li>内容4</li>
    </ul>
</div>

    <div class="tab">
        <ul class="tab-header clearfix">
            <li class="active">选项1</li>
            <li>选项2</li>
            <li>选项3</li>
            <li>选项4</li>
        </ul>
        <ul class="tab-container">
            <li class="active">内容1</li>
            <li>内容2</li>
            <li>内容3</li>
            <li>内容4</li>
        </ul>
    </div>

    <div class="tab">
        <ul class="tab-header clearfix">
            <li class="active">选项1</li>
            <li>选项2</li>
            <li>选项3</li>
            <li>选项4</li>
        </ul>
        <ul class="tab-container">
            <li class="active">内容1</li>
            <li>内容2</li>
            <li>内容3</li>
            <li>内容4</li>
        </ul>
    </div>
    <div class="tab">
        <ul class="tab-header clearfix">
            <li class="active">选项1</li>
            <li>选项2</li>
            <li>选项3</li>
            <li>选项4</li>
        </ul>
        <ul class="tab-container">
            <li class="active">内容1</li>
            <li>内容2</li>
            <li>内容3</li>
            <li>内容4</li>
        </ul>
    </div>
    <script>
        function Tab(ct){
            this.ct = ct;
            this.init();
            this.bind();
        }


        Tab.prototype.init = function(){
            this.tabLis = this.ct.querySelectorAll('.tab-header>li');
            this.tabPanels = this.ct.querySelectorAll('.tab-container>li');
        };


        Tab.prototype.bind = function(){
            var _this = this;
            this.tabLis.forEach(function(tabli){
                tabli.onclick = function(e){
                    var target = e.target;
                    var index = [].indexOf.call(_this.tabLis,target);
                    _this.tabLis.forEach(function(li){
                        li.classList.remove('active');
                    })
                    target.classList.add('active');

                    _this.tabPanels.forEach(function(panel){
                        panel.classList.remove('active');
                    })
                    _this.tabPanels[index].classList.add('active');
                }
            })
        };


        var tab1 = new Tab(document.querySelectorAll('.tab')[0]);
        var tab2 = new Tab(document.querySelectorAll('.tab')[1]);
        var tab3 = new Tab(document.querySelectorAll('.tab')[2]);
        var tab4 = new Tab(document.querySelectorAll('.tab')[3]);
    </script>
</body>
</html>