//获取左右按钮 let left = document.querySelector('div').firstElementChild let right = document.querySelector('div').lastElementChild //点击左按钮，索引减少，图片切到上一张 left.onclick = function() { index-- move(ul, 'left', -index * wrap_width, movend) } //点击右按钮，索引增加，图片切到下一张 right.onclick = function() { index++ move(ul, 'left', -index * wrap_width, movend) }
7、点击焦点切换图片
for (let i = 0; i < ol.children.length; i++) { //获取焦点索引 ol.children[i].id = i //点击焦点切换图片 ol.children[i].onclick = function() { index = this.id - 0 + 1 move(ul, 'left', -index * wrap_width, movend) } }
8、解决切屏后定时器混乱问题
9、解决点击太快定时器混乱问题
添加开关，点击前关着，点击后图片未切换完成开着，图片切换完打开开关，将语句添加进点击事件函数中即可
if (flag) return flag = true
四 全部代码
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>轮播图21</title> <style> * { margin: 0; padding: 0; } ul, ol, li { list-style: none; } a { text-decoration: none; } section { width: 300px; margin: 30px auto; height: 200px; border: 5px solid; position: relative; overflow: hidden; } ul { width: 300%; height: 100%; text-align: center; line-height: 200px; font-size: 100px; position: absolute; top: 0; left: 0; } li { width: 300px; height: 100%; float: left; } ol { width: 150px; height: 20px; position: absolute; bottom: 20px; left: 50%; transform: translateX(-50%); border-radius: 15px; display: flex; justify-content: space-evenly; align-items: center; } ol li { width: 15px; height: 15px; background-color: ivory; border-radius: 50%; } .active { background-color: purple; } div { position: absolute; font-size: 20px; height: 30px; width: 100%; top: 50%; transform: translateY(-50%); display: flex; justify-content: space-between; align-items: center; } div a { background-color: rgba(0, 0, 0, 0.2); width: 30px; } div a:active { background-color: rgba(0, 0, 0, 0.5); } </style> </head> <body> <!-- 布局 --> <section> <ul> <li>1</li> <li>2</li> <li>3</li> </ul> <ol></ol> <div> <a href="javascript:;" ><</a> <a href="javascript:;" >></a> </div> </section> <script> </script> <script> //自动播放函数，每隔两秒切换一次图片 function autoplay() { move_time = setInterval(() => { index++ move(ul, 'left', -index * wrap_width, movend) }, 2000) } //运动函数，设置图片切换方式 //参数ele，元素；type，元素属性；value，元素运动结束时属性值；cb()，元素运动结束函数 function move(ele, type, value, cb) { //获取元素属性初始值 let spe = parseInt(getComputedStyle(ele)[type]) //元素属性改变过程 change_timer = setInterval(() => { value > spe ? spe += 10 : spe -= 10 ele.style[type] = spe + 'px' if (value > spe) { if (spe >= value) { clearInterval(change_timer) cb() } } else { if (spe <= value) { clearInterval(change_timer) cb() } } }, 10) } //运动结束函数 //判断索引临界值，更改索引，更改盒子位置，使图片轮播 //让焦点和图片配套 function movend() { if (index >= ul.children.length - 1) { index = 1 ul.style.left = -index * wrap_width + 'px' } if (index <= 0) { index = ol.children.length ul.style.left = -index * wrap_width + 'px' } for (let i = 0; i < ol.children.length; i++) { ol.children[i].className = '' } ol.children[index - 1].className = 'active' flag = false } //1、获取盛放图片的盒子和盛放焦点的盒子 let ul = document.querySelector('ul') let ol = document.querySelector('ol') //获取大盒子和大盒子的宽 let wrap = document.querySelector('section') let wrap_width = wrap.clientWidth //9、解决连续点击页面混乱问题 //添加开关，点击前关着，点击后图片未切换完成开着，图片切换完打开开关 let flag = false //2、添加焦点 const frg = document.createDocumentFragment() for (let i = 0; i < ul.children.length; i++) { let focus = document.createElement('li') frg.appendChild(focus) //焦点初始化 if (i == 0) focus.className = 'active' } ol.appendChild(frg) //3、复制元素，将复制元素放在指定位置 //改变盛放图片的盒子大小,改变图片位置，使页面打开时显示第一张图片 let first = ul.firstElementChild.cloneNode(true) let last = ul.lastElementChild.cloneNode(true) ul.appendChild(first) ul.insertBefore(last, ul.firstElementChild) ul.style.width = ul.children.length * 100 + '%' ul.style.left = -wrap_width + 'px' //4、图片自动轮播 //设置一个图片索引 let index = 1 //一会儿会用到这段代码，就直接封装成函数了 autoplay() //5、鼠标移入停播，移出开始播放 wrap.onmouseover = () => clearInterval(move_time) wrap.onmouseout = () => autoplay() //6、点击左右按钮切换图片 //获取左右按钮 let left = document.querySelector('div').firstElementChild let right = document.querySelector('div').lastElementChild //点击左按钮，索引减少，图片切到上一张 left.onclick = function() { if (flag) return index-- move(ul, 'left', -index * wrap_width, movend) flag = true } //点击右按钮，索引增加，图片切到下一张 right.onclick = function() { if (flag) return index++ move(ul, 'left', -index * wrap_width, movend) flag = true } //7、点击焦点切换图片 for (let i = 0; i < ol.children.length; i++) { //获取焦点索引 ol.children[i].id = i //点击焦点切换图片 ol.children[i].onclick = function() { if (flag) return index = this.id - 0 + 1 move(ul, 'left', -index * wrap_width, movend) flag = true } } //8、解决切屏后页面混乱问题 document.onvisibilitychange = () => document.visibilityState == 'hidden' ? clearInterval(move_time) : autoplay() </script> </body> </html>