以下代码是扔在module.php里面的，

function em_compress_html_main($buffer){
    $initial=strlen($buffer);
    $buffer=explode("<!--em-compress-html-->", $buffer);
    $count=count ($buffer);
    for ($i = 0; $i <= $count; $i++){
        if (stristr($buffer[$i], '<!--em-compress-html no compression-->')){
            $buffer[$i]=(str_replace("<!--em-compress-html no compression-->", " ", $buffer[$i]));
        }else{
            $buffer[$i]=(str_replace("\t", " ", $buffer[$i]));
            $buffer[$i]=(str_replace("\n\n", "\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;
}

<?php
if(_g('compress_html')=='open'){
        $html=ob_get_contents();
        ob_get_clean();
        echo em_compress_html_main($html);
}
?>

'compress_html' => array(
        'type' => 'radio',
        'name' => '网站源码压缩',
        'description' => '',
        'values' => array('open' => '压缩','close' => '关闭'),
        'default' => 'open'
    ),

效果图：

想要内容里面的pre不被压缩可使用以下函数：

function unCompress($content){
    if(preg_match_all('/(crayon-|<\/pre>)/i', $content, $matches)) {
        $content = '<!--em-compress-html--><!--em-compress-html no compression-->'.$content;
        $content.= '<!--em-compress-html no compression--><!--em-compress-html-->';
    }
    return $content;
}
unCompress($log_content);

独狼的教程