字符串转入二维数组

字符串转为二维数组
$str = array ( 'digest' => '2012', ), 1 => array ( 'digest' => '2011', ), 2 => array ( 'digest' => '2010', ), 3 => array ( 'digest' => '2009', ), 4 => array ( 'digest' => '2008', ), 5 => array ( 'digest' => '2007', ), ); ?> 

需要转成
Array
(
  [0] => Array
  (
  [digest] => 2012
  )

  [1] => Array
  (
  [digest] => 2011
  )

  [2] => Array
  (
  [digest] => 2010
  )

  [3] => Array
  (
  [digest] => 2009
  )

  [4] => Array
  (
  [digest] => 2008
  )

  [5] => Array
  (
  [digest] => 2007
  )

)
求高人帮忙啊

------解决方案--------------------
你字符串是这样的吗？

$str = "array ( 'digest' => '2012'), 1 => array ( 'digest' => '2011' )........"

是的话

PHP code

 '2012'), 1 => array ( 'digest' => '2011' )";

$arr=explode(',',$str);

$temp=array();

foreach($arr as $key=>$value)
{    
    $arr_temp=explode("'",$value);
    $real_value=$arr_temp[3];
    $temp[$key]['digest'] = $real_value;
}

print_r($temp);
?>