php正则截取字符串

$s=<<<txt<embed src="/fofa/upload/2014-08/05/5.mp4" type="video/x-ms-asf-plugin" width="550" height="400" autostart="false" loop="true" />txt;preg_match('/src="(.+?)"/i', $s, $m);echo $m[1];

$s =<<< TXT字符串的格式是<embed src="/fofa/upload/2014-08/05/5.mp4" type="video/x-ms-asf-plugin" width="550" height="400" autostart="false" loop="true" />这个样子的请问怎么截取src="..."里面的内容呢，也就是红字部分。求指导啊TXT;preg_match_all('/src=([\'"]?)(.+?)\1/is', $s, $m);print_r($m);

Array(    [0] => Array        (            [0] => src="/fofa/upload/2014-08/05/5.mp4"            [1] => src="..."        )    [1] => Array        (            [0] => "            [1] => "        )    [2] => Array        (            [0] => /fofa/upload/2014-08/05/5.mp4            [1] => ...        ))

$s=<<<txt<embed src="/fofa/upload/2014-08/05/5.mp4" type="video/x-ms-asf-plugin" width="550" height="400" autostart="false" loop="true" />txt;preg_match('/src="(.+?)"/i', $s, $m);echo $m[1];