原生js轮播特效

作为一名前端工程师，手写轮播图应该是最基本掌握的技能，以下是我自己原生js写的轮播，欢迎指点批评：

首先css代码

a{text-decoration:none;color:#3DBBF5;} *{ margin: 0; padding: 0; } .wrapper{ width: 400px; height: 300px; margin: 100px auto; } #lunbo{ position: relative; overflow: hidden; } #list{ position: relative; white-space: nowrap; // 这块用行元素模拟，所以才用该属性，块元素可修改这块 } #list span{ display: inline-block; width: 400px; height: 300px; text-align: center; line-height: 300px; font-weight: bold; font-size: 100px; color: #fff; } #buttons{ position: absolute; bottom: 0; text-align: center; width: 100%; height: 40px; line-height: 40px; } #buttons span{ display: inline-block; width: 15px; height: 5px; background: #fff; margin: 0 10px; cursor: pointer; transition: all .5s; } #buttons span.on{ height: 20px; } .arrow{ position: absolute; top: 50%; transform: translateY(-50%); font-size: 80px; font-weight: bold; color: #fff; opacity: .3; transition: all .5s; } .wrapper:hover .arrow{ opacity: 1; } #prev{ left: 10px; } #next{ right: 10px; }

然后HTML代码

<div> <div> <div> <span>5</span><span>1</span><span>2</span><span>3</span><span>4</span><span>5</span><span>1</span> </div> <div> <span index="1"></span> <span index="2"></span> <span index="3"></span> <span index="4"></span> <span index="5"></span> </div> <a href="javascript:;">&lt;</a> <a href="javascript:;">&gt;</a> </div> </div>

最后js代码

window.onload=function () { var lunBo = document.getElementById("lunbo"); var list = document.getElementById("list"); var btn = document.getElementById("buttons").getElementsByTagName('span'); var prev = document.getElementById("prev"); var next = document.getElementById('next'); var interval = 3000; var timer; var index = 1; var animated = false; for (var i=0;i<btn.length;i++) { //按钮加点击事件 btn[i].onclick=function () { if(this.className=='on') //如果是状态按钮直接返回节约资源 { return }; var myIndex =parseInt(this.getAttribute('index'));//获取按钮的index属性值 var offset = -400*(myIndex-index); //根据属性值 计算偏移量 animate(offset) //轮播动画 index = myIndex; // 改变索引值 showBtn(); //显示状态按钮 } } function showBtn () { for (var i=0;i<btn.length;i++) { btn[i].className=''; } btn[index-1].className='on'; } prev.onclick=function () { //上一页事件 if (animated) { //如果是动画状态 直接返回解决bug return; } if (index==1) { index =btn.length; } else{ index-=1; } animate(400); showBtn(); } next.onclick=function () { if (animated) { return; } if (index==btn.length) { index =1; } else{ index+=1; } animate(-400); showBtn(); } function animate(offset) { animated = true; //表示在动画状态 var newLeft = parseInt(list.style.left) + offset; //计算新的left值 var time = 400; //设置动画总时间 var interval = 10; //动画帧时间 var speed = offset/(time/interval); //每帧运动距离 function go () { if ((speed>0 && parseInt(list.style.left)<newLeft) || (speed<0 && parseInt(list.style.left)>newLeft)) { //通过条件判断到它是否还要继续进行动画 list.style.left = parseInt(list.style.left) + speed +'px'; setTimeout(go,interval) } else{ animated = false; //动画状态结束 list.style.left = newLeft + 'px'; //现在的位移 if (parseInt(list.style.left)<-2000) { // 辅助假图 list.style.left = -400 + 'px'; } else if( parseInt(list.style.left)>-400){ list.style.left = -2000 + 'px'; } } } go(); } function play () { timer = setTimeout(function () { next.onclick(); play(); },interval) } play(); function stop () { clearTimeout(timer); } lunBo.onmouseover=stop; lunBo.onmouseout=play; }

以上是所有代码，欢迎指点交流！