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                        /前端開發(fā)
                        
                            /JavaScript
                        
                        /焦點(diǎn)圖輪播特效

老師！我怎么沒有切換的效果。。

<!DOCTYPE html>
<html>
<head>
? ?<meta charset="UTF-8">
? ?<title>query焦點(diǎn)輪播圖</title>
? ?<style type="text/css">
? ? ? ?*{ margin: 0; padding: 0; text-decoration: none;}
? ? ? ?body { padding: 20px;}
? ? ? ?#container { width: 600px; height: 400px; border: 3px solid #333; overflow: hidden; position: relative;}
? ? ? ?#list { width: 4200px; height: 400px; position: absolute; z-index: 1;}
? ? ? ?#list img { float: left;}
? ? ? ?#buttons { position: absolute; height: 10px; width: 100px; z-index: 2; bottom: 20px; left: 250px;}
? ? ? ?#buttons span { cursor: pointer; float: left; border: 1px solid #fff; width: 10px; height: 10px; border-radius: 50%; background: #333; margin-right: 5px;}
? ? ? ?#buttons .on { ?background: orangered;}
? ? ? ?.arrow { cursor: pointer; display: none; line-height: 39px; text-align: center; font-size: 36px; font-weight: bold; width: 40px; height: 40px; ?position: absolute; z-index: 2; top: 180px; background-color: RGBA(0,0,0,.3); color: #fff;}
? ? ? ?.arrow:hover { background-color: RGBA(0,0,0,.7);}
? ? ? ?#container:hover .arrow { display: block;}
? ? ? ?#prev { left: 20px;}
? ? ? ?#next { right: 20px;}
? ?</style>
<script type="text/javascript">
? ?window.onload = function(){
? ?var container = document.getElementById('container');
? ?var list = document.getElementById('list');//獲取列表
? ?var buttons = document.getElementById('buttons').getElementByTagment('span');//獲取按鈕
? ?var prev = document.getElementById('prev');//獲取箭頭
? ?var next = document.getElementById('next');//綁定事件
? ?function animate(offset){
? ?list.style.left = parseInt(list.style.left) + offset + 'px';
? ?}
? ?next.onclick = function(){
? ? ? ? animate(-600);//點(diǎn)擊時(shí)向左移動(dòng)600像素
? ? ? ?}
? ? ? ?prev.onclick = function(){
? ? ? ?animate(600);//點(diǎn)擊時(shí)向右移動(dòng)600像素
? ? }
? ?}
</script>
</head>
<body>

<div id="container">
? ?<div id="list" style="left: -600px;">
? ? ? ?<img src="img/5.jpg" alt="1"/>
? ? ? ?<img src="img/1.jpg" alt="1"/>
? ? ? ?<img src="img/2.jpg" alt="2"/>
? ? ? ?<img src="img/3.jpg" alt="3"/>
? ? ? ?<img src="img/4.jpg" alt="4"/>
? ? ? ?<img src="img/5.jpg" alt="5"/>
? ? ? ?<img src="img/1.jpg" alt="5"/>
? ?</div>
? ?<div id="buttons">
? ? ? ?<span index="1" class="on"></span>
? ? ? ?<span index="2"></span>
? ? ? ?<span index="3"></span>
? ? ? ?<span index="4"></span>
? ? ? ?<span index="5"></span>
? ?</div>
? ?<a href="javascript:;" id="prev" class="arrow"><</a>
? ?<a href="javascript:;" id="next" class="arrow">></a>
</div>

</body>
</html>