字符串处理成数组的有关问题

$str = "aa:1,bb:2,cc:3,dd:4";
parse_str(preg_replace(array('/\w+/', '/:/','/,/'), array('"$0"','=','&'), $str), $ar);
print_r($ar);

------解决方案--------------------
再来二种
PHP code
$str = "aa:1,bb:2,cc:3,dd:4";
foreach(array_chunk(preg_split('/[:,]/', $str), 2) as $t) $ar[$t[0]] = $t[1];
print_r($ar);

------解决方案--------------------
添块砖

PHP code

$str = "aa:1,bb:2,cc:3,dd:4";
preg_replace("#([\w]+):([\d]+)#e", "\$arr['\\1']=\\2\\2", $str);

print_r($arr);
/*
Array
(
    [aa] => 11
    [bb] => 22
    [cc] => 33
    [dd] => 44
)

*/

------解决方案--------------------
PHP code
[User:root Time:14:14:44 Path:/home/liangdong/php]$ php arr.php 
1
2
3
4
[User:root Time:14:14:45 Path:/home/liangdong/php]$ cat arr.php