Get all matches in a preg_match request - php

Question

I'm having the following problem, i have that structure:
$table = '
<table>
<tbody>
<tr valign="top">
<td>foo</td>
<td>bar</td>
</tr>
</tbody>
</table>
<table>
<tbody>
<tr valign="top">
<td>bee</td>
<td>dog</td>
</tr>
</tbody>
</table>';
I'm trying to retrieve an array with all <tr> but with no success. The closest pattern I've could made it, return all messed up.
$pattern = "/<tr valign[^>]*>(.*)<\/tr>/s";
preg_match_all($pattern, $table, $matches, PREG_PATTERN_ORDER);
If i put var_dump($matches), I want an array that returns:
array(
[0] => "<td>foo</td><td>bar</td>",
[1] => "<td>bee</td><td>dog</td>"
);
...or something close to that.
But I receive:
string(301) "
foo
bar
"
<table>
<tbody>
<tr valign="top">
<td>bee</td>
<td>dog</td>
</tr>
</tbody></table>
Anyone know what I'm doing wrong?
Thanks in advance.

Answer 1

You must make your quantifier lazy: .* => .*?
When you use a greedy quantifier, .* will take all possible characters, When you use a lazy quantifier, .*? will take the minimum number of characters.
When you use a lazy quantifier, the regex engine will take characters one by one and test the pattern completion for each character.
When you use a greedy quantifier (default behavior) the regex engine will take all possible characters (until the end in your case) and will backtrack character by character until the pattern completion succeed.
Notes:
It is useless to add PREG_PATTERN_ORDER since it is the default set of preg_match_all.
DOMDocument is probably a more adapted tool to deal with html. Example:
$dom = new DOMDocument();
#$dom->loadHTML($table);
$trs = $dom->getElementsByTagName('tr');
$results = array();
foreach ($trs as $tr) {
if ($tr->hasAttribute('valign')) {
$children = $tr->childNodes;
$tmp = '';
foreach ($children as $child) {
$tmp .= trim($dom->saveHTML($child));
}
if (!empty($tmp)) $results[] = $tmp;
}
}
echo htmlspecialchars(print_r($results, true));