strip_tags() function blacklist rather than whitelist

问题:

I recently discovered the strip_tags() function which takes a string and a list of accepted html tags as parameters.

Lets say I wanted to get rid of images in a string here is an example:

$html = ''; $html = '
This should be bold
'; $html .= '
This is awesome
'; $html .= 'This should be bold';  echo strip_tags($html,"
"); 

returns this:

This should be bold
 
This is awesome
 This should be bold 

consequently I gotten rid of my formatting via and perhaps in the future.

I want a way to blacklist rather than whitelist something like:

echo blacklist_tags($html,""); 

returning:

This should be bold
 
This is awesome
 This should be bold 

Is there any way to do this?

回答1:

If you only wish to remove the tags, you can use DOMDocument instead of strip_tags().

$dom = new DOMDocument(); $dom->loadHTML($your_html_string);  // Find all the  tags $imgs = $dom->getElementsByTagName("img");  // And remove them $imgs_remove = array(); foreach ($imgs as $img) {   $imgs_remove[] = $img; }  foreach ($imgs_remove as $i) {   $i->parentNode->removeChild($i); } $output = $dom->saveHTML(); 

回答2:

You can only do this by writing a custom function. Strip_tags() is considered more secure though, because you might forget to blacklist some tags...

PS: Some example functions can be found in the comments on php.net's strip_tags() page

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