What is the best way to split a string into an array of Unicode characters in PHP?

Question

In PHP, what is the best way to split a string into an array of Unicode characters? If the input is not necessarily UTF-8?

I want to know whether the set of Unicode

Answer 1

I was able to write a solution using mb_*, including a trip to UTF-16 and back in a probably silly attempt to speed up string indexing:

$japanese2 = mb_convert_encoding($japanese, "UTF-16", "UTF-8");
$length = mb_strlen($japanese2, "UTF-16");
for($i=0; $i<$length; $i++) {
    $char = mb_substr($japanese2, $i, 1, "UTF-16");
    $utf8 = mb_convert_encoding($char, "UTF-8", "UTF-16");
    print $utf8 . "\n";
}

I had better luck avoiding mb_internal_encoding and just specifying everything at each mb_* call. I'm sure I'll wind up using the preg solution.