js相关小实例——大图轮播

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
*{ margin:0px auto; padding:0px}
#tp{ 100%; height:350px}
.img{ display:none}
#dian{ 200px; height:15px; position:relative; top:-25px}
.yuan{ 13px; height:13px; float:left; margin-left:20px; border:2px solid #FFF;border-radius:100px; background-color:#FFF}
.yuan:hover{ cursor:pointer}
</style>
</head>

<body>

<div id="tp">

    <img style="display:block" class="img" src="img/1e30e924b899a9015ffb691a1e950a7b0308f5cb.jpg" width="1000" height="350" />
    <img class="img" src="img/0c7abcfc2ba612631d883b6171dcc774.jpg" width="1000" height="350" />
    <img class="img" src="img/969c65ce130ccd17c93a8a6bf2d9fd7c.jpg" width="1000" height="350" />
    <img class="img" src="img/ee797172eb553662868372d70f81dac0.jpg" width="1000" height="350" />
    <img class="img" src="img/benbenla-08c.jpg" width="1000" height="350" />

</div>

<div id="dian">
    <div bs="0" class="yuan" onclick="xianshi(this,'0')"></div>
    <div bs="1" class="yuan" onclick="xianshi(this,'1')"></div>
    <div bs="2" class="yuan" onclick="xianshi(this,'2')"></div>
    <div bs="3" class="yuan" onclick="xianshi(this,'3')"></div>
    <div bs="4" class="yuan" onclick="xianshi(this,'4')"></div>
</div>


<script type="text/javascript">

//图片索引
var sy = 0;

//间隔调用
window.setInterval("Huan()",3000);

//调一下换一个
function Huan()
{
    var img = document.getElementsByClassName("img");
    sy++; //索引加1
    
    //判断是否到了最后一张
    if(sy>=img.length)
    {
        sy=0;
    }
    
    //让所有隐藏
    for(var i=0;i<img.length;i++)
    {
        img[i].style.display="none";
    }
    //让下一张显示
    img[sy].style.display="block";
    
    //换圆点的样式
    var yuan = document.getElementsByClassName("yuan");
    
    for(var j=0;j<yuan.length;j++)
    {
        if(yuan[j].getAttribute("bs")==sy)
        {
            yuan[j].style.backgroundColor = "gray";
        }
        else
        {
            yuan[j].style.backgroundColor = "white";
        }
    }
}

function xianshi(t,s)
{
    sy=s;
    
    var img = document.getElementsByClassName("img");
    //让所有隐藏
    for(var i=0;i<img.length;i++)
    {
        img[i].style.display="none";
    }
    //让下一张显示
    img[s].style.display="block";
    
    //改自身样式
    var yuan = document.getElementsByClassName("yuan");
    
    for(var j=0;j<yuan.length;j++)
    {
        yuan[j].style.backgroundColor="white";
    }
    
    t.style.backgroundColor="gray";
}

</script>
</body>
</html>
结果参考