<?php
$str='<p><img border="0" src="upfiles/2009/07/1246430143_1.jpg" alt=""/></p>';
$pattern="/<[img|IMG].*?src=[\'|\"](.*?(?:[\.gif|\.jpg]))[\'|\"].*?[\/]?>/";
preg_match_all($pattern,$str,$match);
print_r($match);
?>
结果显示：
Array
(
[0] => Array
(
[0] => <img border="0" src="upfiles/2009/07/1246430143_1.jpg" alt=""/>
)
[1] => Array
(
[0] => upfiles/2009/07/1246430143_1.jpg
)
)