焦点图效果
http://www.corange.cn//uploadfiles/1107-3_10516.jpg

演示地址:http://www.corange.cn/demo/3725/index.html
<!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>仿腾讯软件中心焦点图片切换效</title>
<LINK rel=stylesheet type=text/css href="css/js.css">
<SCRIPT type=text/javascript>
var $ = function (id) {
return "string" == typeof id ? document.getElementById(id) : id;
};

var Extend = function(destination, source) {
for (var property in source) {
destination[property] = source[property];
}
return destination;
}

var CurrentStyle = function(element){
return element.currentStyle || document.defaultView.getComputedStyle(element, null);
}

var Bind = function(object, fun) {
var args = Array.prototype.slice.call(arguments).slice(2);
return function() {
return fun.apply(object, args.concat(Array.prototype.slice.call(arguments)));
}
}

var Tween = {
Quart: {
easeOut: function(t,b,c,d){
return -c * ((t=t/d-1)*t*t*t - 1) + b;
}
},
Back: {
easeOut: function(t,b,c,d,s){
if (s == undefined) s = 1.70158;
return c*((t=t/d-1)*t*((s+1)*t + s) + 1) + b;
}
},
Bounce: {
easeOut: function(t,b,c,d){
if ((t/=d) < (1/2.75)) {
return c*(7.5625*t*t) + b;
} else if (t < (2/2.75)) {
return c*(7.5625*(t-=(1.5/2.75))*t + .75) + b;
} else if (t < (2.5/2.75)) {
return c*(7.5625*(t-=(2.25/2.75))*t + .9375) + b;
} else {
return c*(7.5625*(t-=(2.625/2.75))*t + .984375) + b;
}
}
}
}


//容器对象,滑动对象,切换数量
var SlideTrans = function(container, slider, count, options) {
this._slider = $(slider);
this._container = $(container);//容器对象
this._timer = null;//定时器
this._count = Math.abs(count);//切换数量
this._target = 0;//目标值
this._t = this._b = this._c = 0;//tween参数

this.Index = 0;//当前索引

this.SetOptions(options);

this.Auto = !!this.options.Auto;
this.Duration = Math.abs(this.options.Duration);
this.Time = Math.abs(this.options.Time);
this.Pause = Math.abs(this.options.Pause);
this.Tween = this.options.Tween;
this.onStart = this.options.onStart;
this.onFinish = this.options.onFinish;

var bVertical = !!this.options.Vertical;
this._css = bVertical ? "top" : "left";//方向

//样式设置
var p = CurrentStyle(this._container).position;
p == "relative" || p == "absolute" || (this._container.style.position = "relative");
this._container.style.overflow = "hidden";
this._slider.style.position = "absolute";

this.Change = this.options.Change ? this.options.Change :
this._slider[bVertical ? "offsetHeight" : "offsetWidth"] / this._count;
};
SlideTrans.prototype = {
//设置默认属性
SetOptions: function(options) {
this.options = {//默认值
Vertical: true,//是否垂直方向(方向不能改)
Auto: true,//是否自动
Change: 0,//改变量
Duration: 50,//滑动持续时间
Time: 10,//滑动延时
Pause: 4000,//停顿时间(Auto为true时有效)
onStart: function(){},//开始转换时执行
onFinish: function(){},//完成转换时执行
Tween: Tween.Quart.easeOut//tween算子
};
Extend(this.options, options || {});
},
//开始切换
Run: function(index) {
//修正index
index == undefined && (index = this.Index);
index < 0 && (index = this._count - 1) || index >= this._count && (index = 0);
//设置参数
this._target = -Math.abs(this.Change) * (this.Index = index);
this._t = 0;
this._b = parseInt(CurrentStyle(this._slider)[this.options.Vertical ? "top" : "left"]);
this._c = this._target - this._b;

this.onStart();
this.Move();
},
//移动
Move: function() {
clearTimeout(this._timer);
//未到达目标继续移动否则进行下一次滑动
if (this._c && this._t < this.Duration) {
this.MoveTo(Math.round(this.Tween(this._t++, this._b, this._c, this.Duration)));
this._timer = setTimeout(Bind(this, this.Move), this.Time);
}else{
this.MoveTo(this._target);
this.Auto && (this._timer = setTimeout(Bind(this, this.Next), this.Pause));
}
},
//移动到
MoveTo: function(i) {
this._slider.style[this._css] = i + "px";
},
//下一个
Next: function() {
this.Run(++this.Index);
},
//上一个
Previous: function() {
this.Run(--this.Index);
},
//停止
Stop: function() {
clearTimeout(this._timer); this.MoveTo(this._target);
}
};
</SCRIPT>
</head>
<body style="text-align:center">

<DIV id=idContainer2 class=container>
<TABLE id=idSlider2 border=0 cellSpacing=0 cellPadding=0>
<TBODY>
<TR>
<TD class=td_f><A href="http://www.corange.cn" target="_blank"><IMG src="../demo1.jpg"></A></TD>
<TD class=td_f><A href="http://www.corange.cn" target="_blank"><IMG src="../demo2.jpg"></A></TD>
<TD class=td_f><A href="http://www.corange.cn" target="_blank"><IMG src="../demo3.jpg"></A></TD>
<TD class=td_f><A href="http://www.corange.cn" target="_blank"><IMG src="../demo4.jpg"></A></TD>
<TD class=td_f><A href="http://www.corange.cn" target="_blank"><IMG src="../demo5.jpg"></A></TD>
</TR></TBODY></TABLE>
<UL id=idNum class=num></UL>
</DIV>

<SCRIPT>
var forEach = function(array, callback, thisObject){
if(array.forEach){
array.forEach(callback, thisObject);
}else{
for (var i = 0, len = array.length; i < len; i++) { callback.call(thisObject, array[i], i, array); }
}
}

var st = new SlideTrans("idContainer2", "idSlider2", 5, { Vertical: false });

var nums = [];
//插入数字
for(var i = 0, n = st._count - 1; i <= n;){
(nums[i] = $("idNum").appendChild(document.createElement("li"))).innerHTML = ++i;
}

forEach(nums, function(o, i){
o.onmouseover = function(){ o.className = "on"; st.Auto = false; st.Run(i); }
o.onmouseout = function(){ o.className = ""; st.Auto = true; st.Run(); }
})

//设置按钮样式
st.onStart = function(){
forEach(nums, function(o, i){ o.className = st.Index == i ? "on" : ""; })
}
st.Run();
</SCRIPT>


<br><br>
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google_ad_client = "pub-4490194096475053";
/* 728x90, 创建于 08-12-8 */
google_ad_slot = "0403648181";
google_ad_width = 728;
google_ad_height = 90;
//-->
</script>
<script type="text/javascript"
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script></div>
</body>
</html>

原文地址:http://www.corange.cn/archives/2010/11/3725.html