function string2KeyedArray($string, $delimiter = ',', $kv = '=>') {
  if ($a = explode($delimiter, $string)) { // create parts
    foreach ($a as $s) { // each part
      if ($s) {
        if ($pos = strpos($s, $kv)) { // key/value delimiter
          $ka[trim(substr($s, 0, $pos))] = trim(substr($s, $pos + strlen($kv)));
        } else { // key delimiter not found
          $ka[] = trim($s);
        }
      }
    }
    return $ka;
  }
} // string2KeyedArray

$veri = array(
    "renk" => array("siyah","yesil","sari"),
    "beden" => array("S","M","L","XL"),
    "degisken" => array("a","b","c"),
    "degiskenss" => array("ass","bss","css")
);

$ar1='renk=>yesil,beden=>M,degisken=>c,degiskenss=>css';
$icindeolsun = string2KeyedArray($ar1);