php字符串转成数组

/*
4.$m = “woxihuanphp”，编程实现：将字符串分割为单个字符存放到一个数组中,并打印数组?
*/
$m='woxihuanphp';
echo $res=trim(chunk_split($m,1,'.'),'.');
$arr1=explode('.',$res);
var_dump($arr1);

/*方法二 */

$m='woxihuanphp';
$arr=str_split($m);