关闭不完整的href标签

Question

I'm trying to close this kind of string:

$link = 'Hello, welcome to <a href="www.stackoverflow.com';

echo $link;

How to fix the incomplete href tag? I want it to be:

$link = 'Hello, welcome to <a href="www.stackoverflow.com"></a>'; // no value between <a> tag is alright.

I don't want to use strip_tags() or htmlentities() because i want it to be displayed as a working link.

Answer 1

Not really good at regex but you can do a workaround using DOMDocument . Example:

$link = 'Hello, welcome to <a href="www.stackoverflow.com';

$output = '';
$dom = new DOMDocument();
libxml_use_internal_errors(true);
$dom->loadHTML($link);
libxml_clear_errors();
// the reason behind this is the HTML parser automatically appends `<p>` tags on lone text nodes, which is weird
foreach($dom->getElementsByTagName('p')->item(0)->childNodes as $child) {
    $output .= $dom->saveHTML($child);
}

echo htmlentities($output);
// outputs:
// Hello, welcome to <a href="www.stackoverflow.com"></a>

Answer 2

Just modify the data as you pull it from mysql. Add to your code that gets the data from mysql something like:

...
$link = < YOUR MYSQL VALUE > . '"></a>';
...

Or you can run a query on your database to update the values, appending the string:

"></a>

Answer 3

You indicated you might be interested in a Regex solution, so here's what I was able to come up with:

$link = 'Hello, welcome to <a href="www.stackoverflow.com';

// Pattern matches <a href=" where there the string ends before a closing quote appears.
$pattern = '/(<a href="[^"]+$)/';

// Perform the regex search
$isMatch = (bool)preg_match($pattern, $link);

// If there's a match, close the <a> tag
if ($isMatch) {
    $link .= '"></a>';
}

// Output the result
echo $link;

Outputs:

Hello, welcome to <a href="www.stackoverflow.com"></a>