PHP: How to close open HTML tag in a string?

Question

I need a solution to this situation please.

Situation is a string that results in something like this:

<p>This is some text and here is a <strong>bold text then the post stop here....</p>

Because the function returns a teaser (summary) of the text, it stops after certain words. Where in this case the tag strong is not closed. But the whole string is wrapped in a paragraph.

Is it possible to convert the above result/output to the following:

<p>This is some text and here is a <strong>bold text then the post stop here....</strong></p>

I do not know where to begin. The problem is that.. I found a function on the web which does it regex, but it puts the closing tag after the string.. therefore it won't validate because I want all open/close tags within the paragraph tags. The function I found does this which is wrong also:

<p>This is some text and here is a <strong>bold text then the post stop here....</p></strong>

Please share your ideas, I am trying everything!

I want to know that the tag can be strong, italic, anything. That's why I cannot append the function and close it manually in the function. Any pattern that can do it for me?

Answer 1

Using a regular expression isn't an ideal approach for this. You should use an html parser instead to create a valid document object model.

As a second option, depending on what you want, you could use a regex to remove any and all html tags from your string before you put it in the <p> tag.

Answer 2

There are numerous other variables that need to be addressed to give a full solution, but are not covered by your question.

However, I would suggest using something like HTML Tidy and in particular the repairFile or repaireString methods.

Answer 3

Here is a function i've used before, which works pretty well:

function closetags($html) {
    preg_match_all('#<(?!meta|img|br|hr|input\b)\b([a-z]+)(?: .*)?(?<![/|/ ])>#iU', $html, $result);
    $openedtags = $result[1];
    preg_match_all('#</([a-z]+)>#iU', $html, $result);
    $closedtags = $result[1];
    $len_opened = count($openedtags);
    if (count($closedtags) == $len_opened) {
        return $html;
    }
    $openedtags = array_reverse($openedtags);
    for ($i=0; $i < $len_opened; $i++) {
        if (!in_array($openedtags[$i], $closedtags)) {
            $html .= '</'.$openedtags[$i].'>';
        } else {
            unset($closedtags[array_search($openedtags[$i], $closedtags)]);
        }
    }
    return $html;
} 

Personally though, I would not do it using regexp but a library such as Tidy. This would be something like the following:

$str = '<p>This is some text and here is a <strong>bold text then the post stop here....</p>';
$tidy = new Tidy();
$clean = $tidy->repairString($str, array(
    'output-xml' => true,
    'input-xml' => true
));
echo $clean;