WordPress 利用代码添加一个文章目录功能

将代码加入到主题 functions.php 中（仅限于H2的标题拿来做文章目录项）

// 文章内容添加文章目录
function content_index($content) {
if(is_single()){
 $matches = array();
 $ul_li = '';
 $r = "/<h2>([^<]+)</h2>/im";
if(preg_match_all($r, $content, $matches)) {
foreach($matches[1] as $num => $title) {
 $content = str_replace($matches[0][$num], '<h2 id="title-'.$num.'">'.$title.'</h2>', $content);
 $ul_li .= '<li><a href="#title-'.$num.'" title="'.$title.'">'.$title."</a></li>n";
}
 $content = "n<div id="article-index"><h3><span>文章目录</span></h3>
 <ul id="index-ul">n" . $ul_li . "</ul>
 </div>n" . $content;rn }
}
return $content;
}
add_filter( "the_content", "content_index", 13 );
// 如果手机端不想显示的话，可以使用(二选一)
if ( !wp_is_mobile()){
 add_filter( "the_content", "content_index", 13 );
}

CSS样式文件仅限参考

#article-index{
 position: fixed;
 z-index: 1;
 top: 30%;
 right: 1%;
 clear: both;
 overflow: hidden;
 background: #FFF;
-webkit-box-shadow: 0 5px 10px 0 rgba(146,146,146,.1);
-moz-box-shadow: 0 5px 10px 0 rgba(146,146,146,.1);
 box-shadow: 0 5px 10px 0 rgba(146,146,146,.1);
 padding: 15px;
 width: 10%;
}
#article-index h3{
 font-size: 18px;
 color: #282828;
 font-weight: 400;
 margin: 0;
 text-transform: uppercase;
 padding-bottom: 10px;
 margin-bottom: 15px;
 position: relative;
}
#article-index h3:after {
 content: "";
 background-color: #19B5FE;
 left: 1px;
 width: 50px;
 height: 2px;
 bottom: -2px;
 position: absolute;
-webkit-transition: 0.5s;
-moz-transition: 0.5s;
-ms-transition: 0.5s;
-o-transition: 0.5s;
 transition: 0.5s;
}
#article-index ul{
 margin: 0 auto;
}
#article-index ul li{
 list-style: none;
}
#article-index ul li a{
 color: #333;
 font-size: 13px;
}
#article-index:hover h3::after{
 width: 70px;
}