$re = '@<a[^>]*href="(?<url>[^"]*(?<=\?|&)o=(?<number>\d+)[^"]*)"[^>]*>\s*last@mis';
$str = '<div class="listing_thumbs_resultcontainer">
<span class="FloatLeft nav-next-btn">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=1&q=nike air&th=1" title="Go to first page">« First</a>
<span class="nav-next-btn nohistory marginLeft">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=18&q=nike air&th=1" title="Go to previous page">
‹ Previous
</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=1&q=nike air&th=1" title="Page 1 of 29">1</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=2&q=nike air&th=1" title="Page 2 of 29">2</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=3&q=nike air&th=1" title="Page 3 of 29">3</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=4&q=nike air&th=1" title="Page 4 of 29">4</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=5&q=nike air&th=1" title="Page 5 of 29">5</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=6&q=nike air&th=1" title="Page 6 of 29">6</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=7&q=nike air&th=1" title="Page 7 of 29">7</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=8&q=nike air&th=1" title="Page 8 of 29">8</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=9&q=nike air&th=1" title="Page 9 of 29">9</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=10&q=nike air&th=1" title="Page 10 of 29">10</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=11&q=nike air&th=1" title="Page 11 of 29">11</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=12&q=nike air&th=1" title="Page 12 of 29">12</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=13&q=nike air&th=1" title="Page 13 of 29">13</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=14&q=nike air&th=1" title="Page 14 of 29">14</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=15&q=nike air&th=1" title="Page 15 of 29">15</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=16&q=nike air&th=1" title="Page 16 of 29">16</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=17&q=nike air&th=1" title="Page 17 of 29">17</a>
</span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=18&q=nike air&th=1" title="Page 18 of 29">18</a>
</span>
<span class="nav-active"><strong>19</strong></span>
<span class="non-active nohistory">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=20&q=nike air&th=1" title="Page 20 of 29">20</a>
</span
</span>
<span class="nav-next-btn nohistory FloatRight">
<span class="nav-next-btn nohistory marginRight">
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=20&q=nike air&th=1" title="Go to next page">
Next ›
</a>
</span>
<a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=29&q=nike air&th=1" title="Go to last page">
Last »
</a>
</span>
</div>';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php