//压缩 html 代码 
function wp_compress_html(){
    function wp_compress_html_main ($buffer){
        $initial=strlen($buffer);
        $buffer=explode("<!--wp-compress-html-->", $buffer);
        $count=count ($buffer);
        for ($i = 0; $i &lt;= $count; $i++){
            if (stristr($buffer[$i], '<!--wp-compress-html no compression-->')) {
                $buffer[$i]=(str_replace("<!--wp-compress-html no compression-->", " ", $buffer[$i]));
            } else {
                $buffer[$i]=(str_replace("t", " ", $buffer[$i]));
                $buffer[$i]=(str_replace("nn", "n", $buffer[$i]));
                $buffer[$i]=(str_replace("n", "", $buffer[$i]));
                $buffer[$i]=(str_replace("r", "", $buffer[$i]));
                while (stristr($buffer[$i], '  ')) {
                    $buffer[$i]=(str_replace("  ", " ", $buffer[$i]));
                }
            }
            $buffer_out.=$buffer[$i];
        }
        $final=strlen($buffer_out);   
        $savings=($initial-$final)/$initial*100;   
        $savings=round($savings, 2);   
        $buffer_out.="n<!--压缩前的大小: $initial bytes; 压缩后的大小: $final bytes; 节约：$savings% -->";   
    return $buffer_out;
}
ob_start("wp_compress_html_main");
}
add_action('get_header', 'wp_compress_html');

<!--wp-compress-html--><!--wp-compress-html no compression-->
此处代码不会被压缩，主要是避免压缩带来的错误，比如 JS 错误
<!--wp-compress-html no compression--><!--wp-compress-html-->

//自动在存在高亮代码的文章首尾插入免压缩注释
  function Code_Box($content) {
    $matches = array();
    //一下是匹配高亮代码的关键词，本代码适用于 Crayon Syntax Highlighter 插件，其他插件请自行分析关键词即可
    $c = "/(crayon-|</pre>)/i";
    if(preg_match_all($c, $content, $matches) && is_single()) {
        $content = '<!--wp-compress-html--><!--wp-compress-html no compression-->'.$content;
        $content.= '<!--wp-compress-html no compression--><!--wp-compress-html-->';
     }
    return $content;
}
add_filter( "the_content", "Code_Box" );