How does str_replace work?

Question

PHP

Code like this:

$one = ['a','b'];
$two = ['b', 'a'];
$str = 'ab';
echo str_replace($one, $two, $str);

Outputs aa .
How to force output ba and how does it all work in general?

Answer 1

In your case, all the letters a are replaced by b
, it turns out 'bb',
then all b are changed to a
, it turns out 'aa'

// Выводит: яблорехкорех орех (по вышеуказанной причине)
$letters = array('я', 'о');
$fruit   = array('яблоко', 'орех');
$text    = 'я о';
$output  = str_replace($letters, $fruit, $text);
echo $output;

example from documentation
something like this: I understand that you want something else, but I don’t want to guess. Try to describe what you need.