简易的返回到顶部前端代码

HTML部分

<a class="to-top">↑</a>

CSS部分

.to-top {
	display: none;
	color: #fff;
	background-color: #282828;
	display: inline-block;
	height: 40px;
	width: 40px;
	line-height: 40px;
	text-align: center;
	border-radius: 2px;
	z-index: 101;
	opacity: 0.4;
	cursor: pointer;
    position: fixed;
    right: 38px;
    bottom: 38px;
}

.to-top:hover {
	color: #fff;
	opacity: 1;
}

JS部分

//返回顶部
var sc = $(".to-top");
sc.bind("click", function() {
	$('html,body').animate({
		'scrollTop': 0
	}, 400);
});
$(window).scroll(function() {
	var scrtop = document.body.scrollTop;
	if(scrtop >= 100) {
		sc.show();
	} else {
		sc.fadeOut();
	}
});