Web页面返回顶部代码

篇幅过长，总是不利于操作，返回顶部能更友好的操作。

1.html代码

<div style="display:none;" class="back-to" id="toolBackTop">
     <a title="返回顶部" onclick="window.scrollTo(0,0);return false;" href="#top" class="back-top">返回顶部</a>
</div>

 2.css代码

.back-to {
	bottom: 35px;
	overflow: hidden;
	position: fixed;
	right: 10px;
	width: 110px;
	z-index: 999;
}
.back-to.back-top {
	background: url("back-top.png") no-repeat scroll 0 0 transparent;
	display: block;
	float: right;
	height: 50px;
	margin-left: 10px;
	outline: 0 none;
	text-indent: -9999em;
	width: 50px;
}
.back-to.back-top:hover {
	background-position: -50px 0
}

  

 3.jquery代码

$(document).ready(function () {
	var bt = $('#toolBackTop');
	var sw = $(document.body)[0].clientWidth;
 
	var limitsw = (sw - 880) / 2 - 80;
	if (limitsw > 0){
		limitsw = parseInt(limitsw);
		bt.css("right",limitsw);
	}
 
	$(window).scroll(function() {
		var st = $(window).scrollTop();
		if(st > 30){
			bt.show();
		}else{
			bt.hide();
		}
	});
})

 

 4.图片