<script language="javascript">
function smartFloat(obj) {
var obj = document.getElementById(obj);
var top = getTop(obj);
var isIE6 = /msie 6/i.test(navigator.userAgent);
window.onscroll = function () {
var bodyScrollTop = document.documentElement.scrollTop || document.body.scrollTop;
if (bodyScrollTop > top) {
obj.style.position = (isIE6) ? "absolute" : "fixed";
obj.style.top = (isIE6) ? bodyScrollTop + "px" : "0px";
} else {
obj.style.position = "static";
}
}
function getTop(e) {
var offset = e.offsetTop;
if (e.offsetParent != null) offset += getTop(e.offsetParent);
return offset;
}
}
window.onload = function () {
smartFloat("nav");
}
$(document).scrollLeft() 这是获取水平滚动条的距离
function smartFloat(obj) {
var obj = document.getElementById(obj);
var top = getTop(obj);
var isIE6 = /msie 6/i.test(navigator.userAgent);
window.onscroll = function () {
var bodyScrollTop = document.documentElement.scrollTop || document.body.scrollTop;
if (bodyScrollTop > top) {
obj.style.position = (isIE6) ? "absolute" : "fixed";
obj.style.top = (isIE6) ? bodyScrollTop + "px" : "0px";
} else {
obj.style.position = "static";
}
}
function getTop(e) {
var offset = e.offsetTop;
if (e.offsetParent != null) offset += getTop(e.offsetParent);
return offset;
}
}
window.onload = function () {
smartFloat("nav");
}
</script>
****扩展*****
//原生JS
//获取div距离顶部的距离
var mTop = document.getElementsByClassName('mdiv')[0].offsetTop;
//获取滚动条的高度 var sTop = document.body.scrollTop;
//Jquery
mTop = $('.mdiv')[0].offsetTop;
sTop = $(window).scrollTop();
$(document).scrollTop() 获取垂直滚动的距离 即当前滚动的地方的窗口顶端到整个页面顶端的距离
$(document).scrollLeft() 这是获取水平滚动条的距离
