PHP将Array转换为String（文件夹和递归）

i am stuck,....

i have an array like this:

$myArray['red'][0] = "valueRed0";
$myArray['red'][1] = "valueRed1";
$myArray['blue'][0] = "valueBlue0";
$myArray['blue'][1] = "valueBlue1";
$myArray['green'][0] = "valueGreen0";
$myArray['green'][1] = "valueGreen1";
$myArray['green'][top][0] = "valueGreenTop0";
$myArray['green'][top][1] = "valueGreenTop1";
$myArray['green'][bottom][0] = "valueGreenBottom0";
$myArray['green'][bottom][1] = "valueGreenBottom1";

As output i need:

array(
'red/valueRed0',
'red/valueRed1',
'blue/valueBlue0',
'blue/valueBlue1',
'green/valueGreen0',
'green/valueGreen1',
'green/top/valueGreenTop0',
'green/top/valueGreenTop1',
'green/bottom/valueGreenBottom0',
'green/bottom/valueGreenButtom1'
)

so this means: if the key is a string, it has to be the folder. If the key is a integer the value has to be ne new value.

It's important that it is recursive to interprate different sized arrays.

Anybody can help me with this, i can't solve this recursive thing.... ?

Here is an example of how it could be done

<?php
$myArray['red'][0] = "valueRed0";
$myArray['red'][1] = "valueRed1";
$myArray['blue'][0] = "valueBlue0";
$myArray['blue'][1] = "valueBlue1";
$myArray['green'][0] = "valueGreen0";
$myArray['green'][1] = "valueGreen1";
$myArray['green']['top'][0] = "valueGreenTop0";
$myArray['green']['top'][1] = "valueGreenTop1";
$myArray['green']['bottom'][0] = "valueGreenBottom0";
$myArray['green']['bottom'][1] = "valueGreenBottom1";

print_r(flatten($myArray));

function flatten($data,$keys=array()){
        $out=array();
        foreach($data as $key=>$val){
                if(!is_array($val)){
                        $out[] = implode("/",$keys)."/".$val;
                }else{
                        $out = array_merge($out,flatten($val,array_merge($keys,array($key))));
                }
        }
        return $out;
}

Output:

Array
(
    [0] => red/valueRed0
    [1] => red/valueRed1
    [2] => blue/valueBlue0
    [3] => blue/valueBlue1
    [4] => green/valueGreen0
    [5] => green/valueGreen1
    [6] => green/top/valueGreenTop0
    [7] => green/top/valueGreenTop1
    [8] => green/bottom/valueGreenBottom0
    [9] => green/bottom/valueGreenBottom1
)