PHP ent_quotes exception for <br> and <ar>

Question

i am trying to covert HTML to entities using PHP, but i need to except <br> and <a> tags.

here's an example of my code

 <?php 
  $string[0] = "<a href='http://hidd3n.tk'>Needs to stay</a> Filler text in between 
 <br><br> <script src='http://malicious.com/'></script> NEEDS to go";
  $string[1] = htmlentities($string[0], ENT_QUOTES, "UTF-8");
 ?>

Answer 1

我建议您使用BBCode ，这样会更安全。

Answer 2

EDIT:

Okay i have worked out a way.

Take this function rather safe than previous one:

function convert_myhtml_entities($string){
    $string = htmlentities($string, ENT_NOQUOTES, "UTF-8");
    $string = preg_replace('/&lt;\s*br\s*(\/|)\s*&gt;/U','<br$1>',$string);
    $string = preg_replace('/&lt;\s*a(.*)\s*&gt;/U','<a$1>',$string);
    $string = preg_replace('/&lt;\s*\/\s*a\s*&gt;/U','</a>',$string);
    return $string;
}

now it is the tested with the string above.