js滑动导航栏点击后居中效果

<!DOCTYPE html>

<html lang="en">

<head>

    <meta charset="UTF-8">

    <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no" />

    <meta http-equiv="X-UA-Compatible" content="ie=edge">

    <title>Document</title>

    <style>

        * {

            margin: 0;

            padding: 0;

        }

        ul {

            list-style: none;

        }

        /* 控制其显示和隐藏 */

        .show {

            display: block !important;

        }

        .header {

            overflow: hidden;

            height: 25px;

            width: 100%;

            height: 25px;

            line-height: 25px;

            padding-bottom: 1px;

        }

        .header-tab {

            width: 100%;

            display: flex;

            overflow: hidden;

            white-space: nowrap;

            overflow-x: scroll;

            background-color: pink;

            white-space: nowrap;

            font-size: 15px;

        }

        .header-tab li {

            cursor: pointer;

            margin-left: 6px;

        }

        .wrapper {

            height: 600px;

            width: 100%;

            margin: 0 auto;

        }

        /* 其子元素为隐藏状态 */

        .wrapper>div {

            display: none;

        }

        /* 隐藏滚动条 */

        .header-tab::-webkit-scrollbar {

            display: none

        }

        /* 添加下划线 */

        .add2line {

            color: #3385ff;

            border-bottom: 1px solid #3385ff;

        }

    </style>

</head>

<body>

    <nav class="header">

        <ul class="header-tab" id="box">

            <li class="add2line">更新内容</li>

            <li>关注</li>

            <li>热点</li>

            <li>要闻</li>

            <li>我的生活</li>

            <li>国际新闻</li>

            <li>态度公开课</li>

            <li>新时代</li>

            <li>抖音视频</li>

        </ul>

    </nav>

    <main class="wrapper">

        <div class="show content">

            页面1

        </div>

        <div class="content">

            页面2

        </div>

        </div>

        <div class="content">

            页面3

        </div>

        <div class="content">

            页面4

        </div>

        <div class="content">

            页面5

        </div>

        <div class="content">

            页面6

        </div>

        <div class="content">

            页面7

        </div>

        <div class="content">

            页面8

        </div>

        <div class="content">

            页面9

        </div>

    </main>

</body>

</html>

<script>

    window.onload = function () {

        var doc = document

        isShow()

        function isShow() {

            var liArr = doc.querySelectorAll('#box > li')

            var divArr = doc.querySelectorAll('.wrapper .content')

            for (var i = 0; i < liArr.length; i++) {

                liArr[i].index = i;

                liArr[i].onclick = function () {

                    for (var j = 0; j < liArr.length; j++) {

                        liArr[j].className = ''

                        divArr[j].className = ''

                    }

                    divArr[this.index].className = 'show'

                    liArr[this.index].className = 'add2line'

                }

            }

        }

        // 当前视窗的宽度

        var WINDOW_OFFSETWIDTH = doc.documentElement.clientWidth

        var liArr = doc.querySelectorAll('#box > li')

        for (var i = 0; i < liArr.length; i++) {

            liArr[i].addEventListener('click', function (e) {

                // 获取当前点击元素的宽度

                var itemWidth = this.offsetWidth

                // 当前事件对象相对移动的距离

                var moveX = e.target.offsetLeft

                // 目标居中的距离 = (当前元素距离左边的相对距离 / 2)+ (视口距离 / 2)

                var left = moveX - (WINDOW_OFFSETWIDTH / 2) + (itemWidth / 2)

                doc.getElementById('box').scrollLeft = left

            })

        }

    }

</script>