如何使用js实现轮播图
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2022-08-01 23:27:36
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="x-ua-compatible" content="ie=edge">
<title>图片切换</title>
<style>
.picture {
position: relative;
width: 500px;
height: 333px;
margin: 0 auto;
border: 2px solid rgb(231, 127, 217);
overflow: hidden;
}
.radius { /* 圆点所在的p (容器) */
width: 100%;
height: 10px;
position: absolute;
bottom: 30px;
text-align: center;
}
.p
g {
position: absolute;
margin: 0;
width: 100%;
height: 20px;
background-color: rgba(0, 0, 0, .4);
text-align: center;
font-size: 16px;
font-weight: 600;
color: #fff;
}
.title {
position: absolute;
width: 100%;
bottom: 0px;
text-align: center;
font-size: 16px;
font-weight: 600;
color: rgb(21, 223, 72);
}
span {
display: inline-block;
border: 10px solid #fdfdfd;
border-radius: 50%;
}
.active {
border: 10px solid #656466;
}
/* 左右箭头 */
.arrowhead-left,
.arrowhead-right {
position: absolute;
width: 41px;
height: 69px;
font-size: 30px;
line-height: 70px;
text-align: center;
color: #d6d8d4;
background-color: rgba(0,0,0,.3);
}
.arrowhead-left {
left: 0;
top: 40%;
}
.arrowhead-right {
right: 0;
top: 40%;
}
</style>
</head>
<body>
<div class="picture">
<!-- 图片页码 -->
<p class="pg">封面</p>
<img src="./image/d8.jpeg" alt="">
<!-- 小圆点点 -->
<p class="radius"></p>
<!-- 图片的下面标题 -->
<p class="title">标题</p>
<!-- 左右箭头 -->
<div class="arrowhead-left" id="al"> < </div>
<div class="arrowhead-right" id="ar"> > </div>
</div>
<script>
var address = ["./image/d1.jpeg", "./image/d2.jpeg", "./image/d3.jpeg", "./image/d4.jpeg", "./image/d5.jpeg", "./image/d7.jpeg"];
// var imgs = document.getelementsbytagname("img");
var imgs = document.queryselector("img");
var len = address.length; //图片地址的数量为len
var str = "";
var pp = document.getelementsbytagname("p");//获取的是p标签的集合
// var pp = document.queryselector("p"); //获取的是一个元素
var al = document.getelementbyid("al");
var ar = document.getelementbyid("ar");
var n = 0 ;
//添加span标签（小圆点），个数为len个
for (i = 0; i < len; i++) {
str += ' <span></span>'
}
pp[1].innerhtml = str;
var spans = pp[1].getelementsbytagname('span'); //获取p[1]里所有span标签
spans[0].classname = 'active'; //给第一个span标签添加样式 active
for (i = 0; i < len; i++) {
spans[i].index = i; //自定义索引值
spans[i].onmouseover = function () { //鼠标指向圆点时的事件
for (i = 0; i < len; i++) {
spans[i].classname = ""; //通过循环，清除所有圆点的类名
}
n=this.index ;
this.classname = 'active'; //给鼠标移入的圆点添加类名
imgs.src = address[this.index];
pp[0].innerhtml = [this.index + 1] + "/6";
pp[2].innerhtml = "风光" + [this.index + 1];
}
}
ar.onclick = function () { //右侧箭头，点击一次图片向右换一张
n++;
if (n>5) {
n=0;
}
for (i = 0; i < len; i++) {
spans[i].classname = "";
}
spans[n].classname = "active";
imgs.src = address[n];
pp[0].innerhtml = (n+1) + "/6";
pp[2].innerhtml = "风光" +(n+1);
}
al.onclick = function () { // //左侧箭头，点击一次图片向左换一张
n--;
if (n<0) {
n=(len-1);
}
for (i = 0; i < len; i++) {
spans[i].classname = "";
}
spans[n].classname = "active";
imgs.src = address[n];
pp[0].innerhtml = (n+1) + "/6";
pp[2].innerhtml = "风光" +(n+1);
}
setinterval(ar.onclick,3000); //添加定时器 setinterval（函数，间隔时间单位为毫秒）
//此次添加的函数为点击右侧箭头，间隔为3秒
</script>
</body>
</html>