参考：
<!-- 目录索引列表生成 -->
<script language="javascript" type="text/javascript">
function GenerateContentList()
{
if ($('#cnblogs_post_body').length == 0) { return; }
var jquery_h1_list = $('#cnblogs_post_body h1');
var jquery_h2_list = $('#cnblogs_post_body h2');
var jquery_h3_list = $('#cnblogs_post_body h3');
if (jquery_h1_list.length != 0)
{
var content = '<a name="_labelTop"></a>';
content += '<div id="navCategory">';
content += '<p style="font-size:18px"><b>目录</b></p>';
content += '<ul class="first_class_ul">';
for (var i = 0; i < jquery_h1_list.length; i++)
{
var go_to_top = '<div style="text-align: right"><a href="#_labelTop">返回目录</a><a name="_label' + i + '"></a></div>';
$(jquery_h1_list[i]).before(go_to_top);
var li_content = '<li><a href="#_label' + i + '">' + $(jquery_h1_list[i]).text() + '</a></li>';
var nextH1Index = i + 1;
if (nextH1Index == jquery_h1_list.length) { nextH1Index = 0; }
var jquery_h2_list = $(jquery_h1_list[i]).nextUntil(jquery_h1_list[nextH1Index], "h2");
if (jquery_h2_list.length > 0)
{
li_content += '<ul class="second_class_ul">';
}
for (var j = 0; j < jquery_h2_list.length; j++)
{
var go_to_top2 = '<div style="text-align: right"><a href="#_labelTop">返回目录</a><a name="_lab2_'+ i + '_' + j + '"></a></div>';
$(jquery_h2_list[j]).before(go_to_top2);
li_content +='<li><a href="#_lab2_'+ i +'_' + j + '">' + $(jquery_h2_list[j]).text() + '</a></li>';
var nextH2Index = j + 1;
var next;
if (nextH2Index == jquery_h2_list.length)
{
if (i + 1 == jquery_h1_list.length)
{
next = jquery_h1_list[0];
}
else
{
next = jquery_h1_list[i + 1];
}
}
else
{
next = jquery_h2_list[nextH2Index];
}
var jquery_h3_list = $(jquery_h2_list[j]).nextUntil(next, "h3");
if (jquery_h3_list.length > 0)
{
li_content += '<ul class="third_class_ul">';
}
for (var k = 0; k < jquery_h3_list.length; k++)
{
var go_to_third_Content = '<div style="text-align: right"><a href="#_labelTop">返回目录</a><a name="_label3_' + i + '_' + j + '_' + k + '"></a></div>';
$(jquery_h3_list[k]).before(go_to_third_Content);
li_content += '<li><a href="#_label3_' + i + '_' + j + '_' + k + '">' + $(jquery_h3_list[k]).text() + '</a></li>';
}
if (jquery_h3_list.length > 0)
{
li_content += '</ul>';
}
li_content += '</li>';
}
if (jquery_h2_list.length > 0)
{
li_content +='</ul>';
}
li_content +='</li>';
content += li_content;
}
content += '</ul>';
content += '</div>';
}
else if (jquery_h2_list.length != 0)
{
var content = '<a name="_labelTop"></a>';
content += '<div id="navCategory">';
content += '<p style="font-size:18px"><b>目录</b></p>';
content += '<ul class="second_class_ul">';
for(var i =0; i < jquery_h2_list.length; i++)
{
var go_to_top2 = '<div style="text-align: right"><a href="#_labelTop">返回目录</a><a name="_lab2_'+ i + '_' + j + '"></a></div>';
$(jquery_h2_list[j]).before(go_to_top2);
var li_content = '<li><a href="#_lab' + i + '">' + $(jquery_h2_list[i]).text() + '</a></li>';
var nextH1Index = i + 1;
if (nextH1Index == jquery_h2_list.length) { nextH1Index = 0; }
var jquery_h3_list = $(jquery_h2_list[i]).nextUntil(jquery_h2_list[i+1], "h3");
if(jquery_h3_list.length>0)
{
li_content +='<ul class="third_class_ul">';
}
for(var j = 0;j < jquery_h3_list.length;j++)
{
var go_to_third_Content = '<div style="text-align: right"><a href="#_labelTop">返回目录</a><a name="_label3_' + i + '_' + j + '_' + k + '"></a></div>';
$(jquery_h3_list[k]).before(go_to_third_Content);
li_content +='<li><a href="#_lab2'+ i +'_' + j + '">' + $(jquery_h3_list[j]).text() + '</a></li>';
}
if(jquery_h3_list.length>0)
{
li_content +='</ul>';
}
li_content +='</li>';
content += li_content;
}
content += '</ul>';
content += '</div>';
}
else if (jquery_h3_list.length != 0)
{
var content = '<a name="_labelTop"></a>';
content += '<div id="navCategory">';
content += '<p style="font-size:18px"><b>目录</b></p>';
content += '<ul>';
for(var i = 0; i < jquery_h3_list.length; i++)
{
var go_to_third_Content = '<div style="text-align: right"><a href="#_labelTop">返回目录</a><a name="_label3_' + i + '_' + j + '_' + k + '"></a></div>';
$(jquery_h3_list[k]).before(go_to_third_Content);
var li_content = '<li><a href="#_label' + i + '">' + $(jquery_h3_list[i]).text() + '</a></li>';
content += li_content;
}
content += '</ul>';
content += '</div>';
}
else
{
return;
}
$($('#cnblogs_post_body')[0]).prepend(content);
}
GenerateContentList();
</script>
自定义CSS：(位置和背景颜色，以及超链接的下划线)
div#navCategory {
position: fixed;
left: 0;
top: 20px;
300px;
background-color:white;
}
#cnblogs_post_body a:link {
text-decoration: none;
}
效果：
补丁 2019/8/28
侧边栏目录有个问题，在15.6的显示器上会出现遮挡情况。（当初设置的时候是用23寸显示器来写的）
于是在目录旁边加了一个隐藏显示的切换功能。
贴一下代码
<b>目录/</b><b class="hide">隐藏</b></p>';
然后JS设置一个滑动滑出的功能：
<script>
$(document).ready(function(){
$(".hide").click(function(){
$("#navCategory ul").slideToggle();
if($(".hide").text()=="隐藏")
{
$(".hide").text("显示");
}
else
{
$(".hide").text("隐藏");
}
});
});
</script>