Sort strings, first letters first, then letters inside words

Question

I would like to sort strings in PHP, and the match should be done foremost on the first letters of a substring, then on the letters of the whole the string.

For example, if someone searches do, and the list contains

Adolf
Doe
Done

the result should be

Doe
Done
Adolf

Using the regular sort($array, SORT_STRING) or things like that does not work, Adolf is sorted before the others.

Does someone have an idea how to do that ?

Answer 1

usort(array, callback) lets you sort based on a callback.

example (something like this, didn't try it)

usort($list, function($a, $b) {
   $posa = strpos(tolower($a), 'do');
   $posb = strpos(tolower($b), 'do');
   if($posa != 0 && $posb != 0)return strcmp($a, $b);
   if($posa == 0 && $posb == 0)return strcmp($a, $b);
   if($posa == 0 && $posb != 0)return -1;
   if($posa != 0 && $posb == 0)return 1;
});