<!doctype html>
<html>
<head>
<meta http-equiv="Content-Type" c />
<meta name="auther" c />
<title>图片放大缩小</title>
<script type="text/javascript">
// 放大缩小控制
var PhotoSize = {
zoom: 0, // 缩放率
count: 0, // 缩放次数
cpu: 0, // 当前缩放倍数值
elem: "", // 图片节点
photoWidth: 0, // 图片初始宽度记录
photoHeight: 0, // 图片初始高度记录
init: function(){
this.elem = document.getElementById("focusphoto");
this.photoWidth = this.elem.scrollWidth;
this.photoHeight = this.elem.scrollHeight;
this.zoom = 1.2; // 设置基本参数
this.count = 0;
this.cpu = 1;
},
action: function(x){
if(x === 0){
this.cpu = 1;
this.count = 0;
}else{
this.count += x; // 添加记录
this.cpu = Math.pow(this.zoom, this.count); // 任意次幂运算
};
this.elem.style.width = this.photoWidth * this.cpu +"px";
this.elem.style.height = this.photoHeight * this.cpu +"px";
}
};
// 启动放大缩小效果 用onload方式加载,防止第一次点击获取不到图片的宽高
window.onload = function(){PhotoSize.init()};
</script>
</head>
<body>
<input type="button" value="放大" > <input type="button" value="缩小" > <input type="button" value="还原大小" > <input type="button" value="查看当前倍数" ><br>
<img id="focusphoto" src="/docimg/201111/24/1354009769.jpg">
</body>
</html>