<html><head><title>jquery实现章节目录效果</title>
<script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.2.min.js"></script>
<style>
body{background-attachment:fixed;background-image:url(about:blank)}/*修正IE6下浮动层闪动*/
#anchor{position:fixed;top:150px;right:0px;border:solid 1px black;}
#anchor.fixie6{position:absolute;top:expression(eval(document.documentElement.scrollTop)+150);}
#anchor a{text-decoration:none;color:blue;}
#anchor a.focus{background:red;color:white;}
</style>
<script>
if (document.all) document.write('<!--[if lte IE 6]><script type="text/javascript">window.fixIE6= true<\/script><![endif]-->');//增加是否为IE6的判断
window.onload = function () {
var strict = document.compatMode == 'CSS1Compat', contents = $('div>a[name]:first-child'), anchors, s = [];
contents.each(function () { s[s.length] = '<a href="#' + this.name + '">' + this.name + '</a>'; });
anchors = $('<div id="anchor"' + (window.fixIE6 ? ' class="fixie6"' : '') + '>' + s.join('<br>') + '</div>').appendTo(document.body).find('a'); //添加文章的章节目录
contents = contents.parent(); //更新章节锚点为内容节点
//计算内容节点的上端点和下端点
contents.each(function () { var o = $(this); o.data('top-bottom', { top: o.offset().top, bottom: o.offset().top + o.height() }); });
$(window).scroll(function () {
var viewTop = Math.max(document.body.scrollTop, document.documentElement.scrollTop); //可见高度顶部
var viewBottom = document[strict ? 'documentElement' : 'body'].clientHeight + viewTop; //可见高度底部
contents.each(function (index, el) {
var tb = $(this).data('top-bottom');
if ((tb.top > viewTop && tb.top < viewBottom) || (tb.bottom > viewTop && tb.bottom < viewBottom) || (tb.top < viewTop && tb.bottom > viewBottom))
anchors.eq(index).addClass('focus');
else
anchors.eq(index).removeClass('focus');
}).trigger('scroll');
});
};
</script>
</head><body><div style="height:800px"><a name="anchor1">anchor1</a></div>
<div style="height:800px"><a name="anchor2">anchor2</a></div>
<div style="height:800px"><a name="anchor3">anchor3</a></div>
<div style="height:800px"><a name="anchor4">anchor4</a></div><div id="anchor"><a href="#anchor1" class="focus">anchor1</a><br><a href="#anchor2" class="focus">anchor2</a><br><a href="#anchor3" class="">anchor3</a><br><a href="#anchor4" class="">anchor4</a></div></body></html>