请教个正则

Question

http://www.xxx.com/view.php?id=5299542513&cid=1512
我想匹配上面字符“&cid”前5位数字，请教正则怎么写，谢谢

Answer 1

<?php
$string = <<<CONT
http://www.xxx.com/view.php?id=5299542513&cid=1512
CONT;
preg_match_all('/(.{5})&cid/is', $string, $matches);
print_r($matches[1]);
?>

Answer 2

$str = "http://www.xxx.com/view.php?id=5299542513&cid=1512";preg_match_all('|(.{5})&cid|is', $str, $arr, PREG_PATTERN_ORDER);
echo $arr[1][0];