一、JS Code：
<script type="text/javascript">
$.fn.smartFloat = function () {
var position = function (element) {
var top = element.position().top, pos = element.css("position");
$(window).scroll(function () {
var scrolls = $(this).scrollTop();
if (scrolls > top) {
if (window.XMLHttpRequest) {
element.css({
position: "fixed",
top: 0
});
} else {
element.css({
top: scrolls
});
}
} else {
element.css({
position: pos,
top: top
});
}
});
};
return $(this).each(function () {
position($(this));
});
};
//绑定
$("#float").smartFloat();
</script>
二、Html Code：
<div class="float" id="float" style="border: 1px solid #e0e0e0; padding: 10px;">
我是置顶时悬浮的区域</div>
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