PHP-Methode „strip_tags' zum Beibehalten mehrerer HTML-Tags

echo strip_tags($str, "<p> <b>"); 
// 输出：<p>我来自<b>PHP中文网</b></p>

function strip_selected_tags($text, $tags = array()) {
  $args = func_get_args();
  $text = array_shift($args);
  $tags = func_num_args() > 2 ? array_diff($args, array($text)) : (array) $tags;
  foreach($tags as $tag) {
    if (preg_match_all(&#39;/<&#39;.$tag.
        &#39;[^>]*>([^<]*)</&#39;.$tag.
        &#39;>/iu&#39;, $text, $found)) {
      $text = str_replace($found[0], $found[1], $text);
    }
  }
 
  return preg_replace(&#39;/(<(&#39;.join(&#39;|&#39;, $tags).
    &#39;)( | |.)*/>)/iu&#39;, &#39;&#39;, $text);
}
 
$str = "[url="] 123[/url]";
    echo strip_selected_tags($str, array(&#39;b&#39;));