web前端js实现动态改变焦点图大小

以下就是实现改变焦点图大小功能的步骤：
<style>
.flexslider {
	margin: 0px auto;
	position: relative;
	width: 100%;
	overflow: hidden;
	zoom: 1;
	max-width:100%;min-width:1309px;
	max-height:100%
}
.flexslider .slides li {
	width: 100%;
	height: 100%;
}
.flex-direction-nav{
	margin-top:-200px;
}
.flex-direction-nav a {
	width: 70px;
	height: 70px;
	line-height: 99em;
	overflow: hidden;
	margin: -35px 0 0;
	display: block;
	background: url(images/ad_ctr.png) no-repeat;
	position: absolute;
	top: 50%;
	z-index: 10;
	cursor: pointer;
	opacity: 0;
	filter: alpha(opacity=0);
	-webkit-transition: all .3s ease;
	border-radius: 35px;
}
.flex-direction-nav .flex-next {
	background-position: 0 -70px;
	right: 470px;
}
.flex-direction-nav .flex-prev {
	left: 470px;
}
.flexslider:hover .flex-next {
	opacity: 0.8;
	filter: alpha(opacity=25);
}
.flexslider:hover .flex-prev {
	opacity: 0.8;
	filter: alpha(opacity=25);
}
.flexslider:hover .flex-next:hover,
.flexslider:hover .flex-prev:hover {
	opacity: 1;
	filter: alpha(opacity=50);
}

.flexslider .slides a img {
	width: 100%;
	display: block;
	max-width:100%;
	height: auto; 
}

.flex-control-nav {
	position: absolute;
	bottom: 60px;left:47%;
	text-align: center;
}
.flex-control-nav li {
	margin: 0 2px;
	display: inline-block;
	zoom: 1;
	*display: inline;
}
.flex-control-paging li a {
	background: url(images/dot.png) no-repeat 0 -16px;
	display: block;
	height: 16px;
	overflow: hidden;
	text-indent: -99em;
	width: 16px;
	cursor: pointer;
}
.flex-control-paging li a.flex-active,
.flex-control-paging li.active a {
	background-position: 0 0;
}
.flexslider .slides a img {
	width: 100%;
	display: block;
	height: auto; 
}

</style>
<div id="banner_tabs" class="flexslider">
	<ul class="slides">
		<li>
			<a href="category.php?id=2">
				<img src="images/focus/10.1.jpg" style="max-width:100%" />
			</a>
		</li>
		<li>
			<a href="zdy1490336173.php">
				<img src="images/focus/JX..jpg" style="max-width:100%" />
			</a>
		</li>
	</ul>
	<ul class="flex-direction-nav">
		<li>
			<a class="flex-prev" href="javascript:;">Previous</a> 
		</li>
		<li>
			<a class="flex-next" href="javascript:;">Next</a> 
		</li>
	</ul>
	<ol id="bannerCtrl" class="flex-control-nav flex-control-paging">
		<li>
			<a>1</a> 
		</li>
		<li>
			<a>2</a> 
		</li>
	</ol>
</div>
<script src="/js/jquery-1.10.2.min.js"></script>
<script src="/js/slider.js"></script>
<script type="text/javascript">
$(function() {
	/*焦点图start*/
	var bannerSlider = new Slider($(‘#banner_tabs‘), {
		time: 5000,
		delay: 400,
		event: ‘hover‘,
		auto: true,
		mode: ‘fade‘,
		controller: $(‘#bannerCtrl‘),
		activeControllerCls: ‘active‘
	});
	$(‘#banner_tabs .flex-prev‘).click(function() {
		bannerSlider.prev()
	});
	$(‘#banner_tabs .flex-next‘).click(function() {
		bannerSlider.next()
	});
　　　　/*焦点图end*/
　　　　/*改这宽度start*/
	var winWidth = 0;  
	var winHeight = 0;  
	function findDimensions() { //函数：获取尺寸  
		//获取窗口宽度  
		if (window.innerWidth) {  
			winWidth = window.innerWidth;  
		}  
		else if ((document.body) && (document.body.clientWidth)) {  
			winWidth = document.body.clientWidth;  
		}  
		//获取窗口高度  
		if (window.innerHeight) {  
			winHeight = window.innerHeight;  
		}  
		else if ((document.body) && (document.body.clientHeight)) {  
			winHeight = document.body.clientHeight;  
		}  
		//通过深入Document内部对body进行检测，获取窗口大小  
		if (document.documentElement && document.documentElement.clientHeight && document.documentElement.clientWidth) {  
			winHeight = document.documentElement.clientHeight-173; //这里是根据当前需要改变的值 
			winWidth = document.documentElement.clientWidth;  
		}              
		//设置div的具体宽度=窗口的宽度的%  
		if (document.getElementById("banner_tabs")) {  
			document.getElementById("banner_tabs").style.height = winHeight + "px";  
		}  
	}  
	findDimensions();  
	window.onresize = findDimensions;
　　　　/*改这宽度end*/
});
</script>
写的比较简陋，如有错的地方，可以联系我哦