How to split a string into characters using preg_split without spaces?

Question

PHP

I'm trying to split the string into characters and put it into an array using preg_split, but spaces are added along with all the characters.
$text = 'plain text';
$text_trim = trim($text);
$str = preg_split('//u',$text_trim,-1,PREG_SPLIT_NO_EMPTY);

Answer 1

$str = preg_split('/\s+|/u', $text_trim, -1, PREG_SPLIT_NO_EMPTY);

Answer 2

$text_trim = preg_replace('/[\s]+/u','',$text);