将字符串拆分为字符对数组

Question

可能重复:
PHP preg_split字符串成字母对

我有一个字符串看起来像这样:

$str = "How are you doing?";

如何将此字符串转换为如下所示的数组:

$arr = array("Ho","w ","ar","r ","yo","u ","do","in","g?");

Answer 1

$array = str_split($str, 2);

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