方法一
代码中的第1、3行分别是针对文章内容、评论内容的，请根据自己的需要选择。比如不需要自动给文章内容的站外链接添加 nofollow 的话，就注销或删除第一行代码，代码直接放fuctions.php中。
add_filter('the_content', 'auto_nofollow'); //nofollow文章内容的站外链接
add_filter('comment_text', 'auto_nofollow'); //nofollow评论内容的站外链接
function auto_nofollow($content) {
//return stripslashes(wp_rel_nofollow($content));
return preg_replace_callback('/<a>]+/', 'auto_nofollow_callback', $content);
}
function auto_nofollow_callback($matches) {
$link = $matches[0];
$site_link = get_bloginfo('url');
if (strpos($link, 'rel') === false) {
$link = preg_replace("%(href=S(?!$site_link))%i", 'rel="nofollow" $1', $link);
} elseif (preg_match("%href=S(?!$site_link)%i", $link)) {
$link = preg_replace('/rel=S(?!nofollow)S*/i', 'rel="nofollow"', $link);
}
return $link;
}
方法二
也是直接放在functions.php
//自动给文章的外部链接添加nofollow属性
add_filter('the_content','_the_content_nofollow',999);
function _the_content_nofollow($content){
preg_match_all('/href="(.*?)"/',$content,$matches);
if($matches){
foreach($matches[1] as $val){
if( strpos($val,home_url())===false ) $content=str_replace("href=\"$val\"", "href=\"$val\" rel=\"external nofollow\" ",$content);
}
}
return $content;
}
文章关键词加粗,这个功能也太简单了，后前研究下依据tag来判断加粗。
//自动给文章关键词加粗
add_filter('the_content','_content_strong');
function _content_strong($content){
$content=str_replace('关键词','<strong>关键词</strong>',$content);
return $content;
}
方法三
这个是依据链接的具体地址来判断的，看是不是内链接，食用方法也是放到functions.php中。
add_filter( 'the_content', '_the_content_nofollow');
function _the_content_nofollow( $content ) {
$regexp = "<a\s[^>]*href=(\"??)([^\" >]*?)\\1[^>]*>";
if(preg_match_all("/$regexp/siU", $content, $matches, PREG_SET_ORDER)) {
if( !emptyempty($matches) ) {
$srcUrl = get_option('siteurl');
for ($i=0; $i < count($matches); $i++)
{
$tag = $matches[$i][0];
$tag2 = $matches[$i][0];
$url = $matches[$i][0];
$noFollow = '';
$pattern = '/target\s*=\s*"\s*_blank\s*"/';
preg_match($pattern, $tag2, $match, PREG_OFFSET_CAPTURE);
if( count($match) < 1 )
$noFollow .= ' target="_blank" ';
$pattern = '/rel\s*=\s*"\s*[n|d]ofollow\s*"/';
preg_match($pattern, $tag2, $match, PREG_OFFSET_CAPTURE);
if( count($match) < 1 )
$noFollow .= ' rel="nofollow" ';
$pos = strpos($url,$srcUrl);
if ($pos === false) {
$tag = rtrim ($tag,'>');
$tag .= $noFollow.'>';
$content = str_replace($tag2,$tag,$content);
}
}
}
}
$content = str_replace(']]>', ']]>', $content);
return $content;
}
function _the_content_nofollow( $content ) {
$regexp = "<a\s[^>]*href=(\"??)([^\" >]*?)\\1[^>]*>";
if(preg_match_all("/$regexp/siU", $content, $matches, PREG_SET_ORDER)) {
if( !emptyempty($matches) ) {
$srcUrl = get_option('siteurl');
for ($i=0; $i < count($matches); $i++)
{
$tag = $matches[$i][0];
$tag2 = $matches[$i][0];
$url = $matches[$i][0];
$noFollow = '';
$pattern = '/target\s*=\s*"\s*_blank\s*"/';
preg_match($pattern, $tag2, $match, PREG_OFFSET_CAPTURE);
if( count($match) < 1 )
$noFollow .= ' target="_blank" ';
$pattern = '/rel\s*=\s*"\s*[n|d]ofollow\s*"/';
preg_match($pattern, $tag2, $match, PREG_OFFSET_CAPTURE);
if( count($match) < 1 )
$noFollow .= ' rel="nofollow" ';
$pos = strpos($url,$srcUrl);
if ($pos === false) {
$tag = rtrim ($tag,'>');
$tag .= $noFollow.'>';
$content = str_replace($tag2,$tag,$content);
}
}
}
}
$content = str_replace(']]>', ']]>', $content);
return $content;
}
给标签云的超链接添加nofollow
add_filter('wp_tag_cloud','tag_cloud_nofollow');
function tag_cloud_nofollow($cloud){
$cloud=preg_replace('/<a /','<a rel="nofollow" ',$cloud);
return $cloud;
}
function tag_cloud_nofollow($cloud){
$cloud=preg_replace('/<a /','<a rel="nofollow" ',$cloud);
return $cloud;
}
方法四
这个是把外链直用base64加密，然后加个跳转，这样看起来好高大上~外链全都是转成跳转的。
add_filter('the_content','yefengs_the_go_url',999);
function yefengs_the_go_url($content){
preg_match_all('/href="(.*?)"/',$content,$matches);
if($matches){
foreach($matches[1] as $val){
if( strpos($val,home_url())===false ) $content=str_replace("href=\"$val\"", "href=\"" . get_bloginfo('wpurl'). "/?home=" .base64_encode($val). "\"",$content);
}
}
return $content;
}
function gohome() {
if ( isset($_GET['home'])) {
$str = $_GET["home"];
if ($str == base64_encode(base64_decode($str)) && !empty($str)) {
header('location:'.base64_decode($str));
}else{
$str=$_SERVER["HTTP_REFERER"];
header('location:'.$str);
}
}
}
add_action('init', 'gohome');
function yefengs_the_go_url($content){
preg_match_all('/href="(.*?)"/',$content,$matches);
if($matches){
foreach($matches[1] as $val){
if( strpos($val,home_url())===false ) $content=str_replace("href=\"$val\"", "href=\"" . get_bloginfo('wpurl'). "/?home=" .base64_encode($val). "\"",$content);
}
}
return $content;
}
function gohome() {
if ( isset($_GET['home'])) {
$str = $_GET["home"];
if ($str == base64_encode(base64_decode($str)) && !empty($str)) {
header('location:'.base64_decode($str));
}else{
$str=$_SERVER["HTTP_REFERER"];
header('location:'.$str);
}
}
}
add_action('init', 'gohome');
方法五
这个也是一样的，这个是加了个从"新窗口"打开外链
add_filter( 'the_content', 'cn_nf_url_parse');
function cn_nf_url_parse( $content ) {
$regexp = "<a\s[^>]*href=(\"??)([^\" >]*?)\\1[^>]*>";
if(preg_match_all("/$regexp/siU", $content, $matches, PREG_SET_ORDER)) {
if( !empty($matches) ) {
$srcUrl = get_option('siteurl');
for ($i=0; $i < count($matches); $i++)
{
$tag = $matches[$i][0];
$tag2 = $matches[$i][0];
$url = $matches[$i][0];
$noFollow = '';
$pattern = '/target\s*=\s*"\s*_blank\s*"/';
preg_match($pattern, $tag2, $match, PREG_OFFSET_CAPTURE);
if( count($match) < 1 )
$noFollow .= ' target="_blank" ';
$pattern = '/rel\s*=\s*"\s*[n|d]ofollow\s*"/';
preg_match($pattern, $tag2, $match, PREG_OFFSET_CAPTURE);
if( count($match) < 1 )
$noFollow .= ' rel="nofollow" ';
$pos = strpos($url,$srcUrl);
if ($pos === false) {
$tag = rtrim ($tag,'>');
$tag .= $noFollow.'>';
$content = str_replace($tag2,$tag,$content);
}
}
}
}
$content = str_replace(']]>', ']]>', $content);
return $content;
}
function cn_nf_url_parse( $content ) {
$regexp = "<a\s[^>]*href=(\"??)([^\" >]*?)\\1[^>]*>";
if(preg_match_all("/$regexp/siU", $content, $matches, PREG_SET_ORDER)) {
if( !empty($matches) ) {
$srcUrl = get_option('siteurl');
for ($i=0; $i < count($matches); $i++)
{
$tag = $matches[$i][0];
$tag2 = $matches[$i][0];
$url = $matches[$i][0];
$noFollow = '';
$pattern = '/target\s*=\s*"\s*_blank\s*"/';
preg_match($pattern, $tag2, $match, PREG_OFFSET_CAPTURE);
if( count($match) < 1 )
$noFollow .= ' target="_blank" ';
$pattern = '/rel\s*=\s*"\s*[n|d]ofollow\s*"/';
preg_match($pattern, $tag2, $match, PREG_OFFSET_CAPTURE);
if( count($match) < 1 )
$noFollow .= ' rel="nofollow" ';
$pos = strpos($url,$srcUrl);
if ($pos === false) {
$tag = rtrim ($tag,'>');
$tag .= $noFollow.'>';
$content = str_replace($tag2,$tag,$content);
}
}
}
}
$content = str_replace(']]>', ']]>', $content);
return $content;
}