作者：Lellansin 转载请标明出处，谢谢
现在我们让滑动多一个功能，三张图、点击左边向左滑动，点右向右滑，碰到临界值的时候可以循环滑动
原理也很将简单，用position:absolute将定位设置成决定定位，通过改变图片相对于绝对位置的坐标来实现滑动。
<!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>js简单的滑动教程（2）</title>
<style type="text/css">
*{ margin:0; padding:0; }
li{ list-style: none; }
#window{ height:200px; width:230px; margin:0 auto; overflow:hidden; }
#center_window{ height:200px; width:160px; float:left; }
#center_window ul{ height:200px; width:160px; position:absolute;overflow:hidden }
#center_window ul li{ height:200px; width:160px; float:left; position:absolute;}
#center_window img{ display:block; margin:5px auto; }
#left_arrow{ height:200px; width:35px; float:left; background:url("left.png") no-repeat scroll 5px 75px #fff; }
#left_arrow:hover{ cursor: pointer; }
#right_arrow{ height:200px; width: 35px; float:right; background:url("right.png") no-repeat scroll 0px 75px #fff; }
#right_arrow:hover{ cursor: pointer; }
</style>
</head>
<body>
<div id="window">
<div id="left_arrow" onclick="sliderLeft()"></div>
<div id="center_window">
<ul>
<li id="list_0"><img src="img/1.jpg" /></li>
<li id="list_1"><img src="img/2.jpg" /></li>
<li id="list_2"><img src="img/3.jpg" /></li>
</ul>
</div>
<div id="right_arrow" onclick="sliderRight()"></div>
</div>
<div id="text" style="margin:0 auto;width:200px;">
</div>
<script>
// 图片总数
var total = 3;
//当所有图片都显示的时候，所有图片的left都=0，这个时候最后一张图会叠最上面，所以计数器从最后一个开始计数
var count = total-1;
function sliderLeft(){
// 拼出当前以及左右图片的id
var left = "list_"+((count+total*100-1)%total);
var center = "list_"+((count+total*100)%total);
var right = "list_"+((count+total*100+1)%total);
// 获取对象
var pic_left = document.getElementById(left);
var pic_center = document.getElementById(center);
var pic_right = document.getElementById(right);
// 设置坐标
pic_left.style.left = -160 + "px";
pic_center.style.left = 0 + "px";
pic_right.style.left = 160 + "px";
var i=0;
var timer = setInterval(function(){
if(i<=160){
//滑动
pic_left.style.left = i-160 + "px";
pic_center.style.left = i + "px";
pic_right.style.left = i+160 + "px";
i+=40;
}else{
clearInterval(timer);
}
},80);
// 计数
count--;
}
function sliderRight(){
// 拼出id
var left = "list_"+((count+total*100-1)%total);
var center = "list_"+((count+total*100)%total);
var right = "list_"+((count+total*100+1)%total);
// 获取对象
var pic_left = document.getElementById(left);
var pic_center = document.getElementById(center);
var pic_right = document.getElementById(right);
//设置坐标
pic_left.style.left = -160 + "px";
pic_center.style.left = 0 + "px";
pic_right.style.left = 160 + "px";
var i=160;
var timer = setInterval(function(){
if(i>=0){
// 滑动
pic_left.style.left = i - 320 + "px";
pic_center.style.left = i - 160 + "px";
pic_right.style.left = i + "px";
i-=40;
}else{
clearInterval(timer);
}
},80);
// 计数
count++;
}
</script>
</body>
</html>
