数组转化成字符串,并原样还原回数组

$str = array
(
    'a' => 'aa',
    'b' => 'bb',
    'c' => array
    (
        0 => 1,
        1 => 2,
        2 => 34,
        3 => 4,
    ),

);
//把数组转化成字符串,可以进行直接存储到数据库中
$s = var_export($str, true);
//从字符串中还原回数组
eval("\$st = $s;");
var_dump($st);