Split utf8 string into array of chars

Question

I\'m trying to split a utf8 encoded string into an array of chars. The function that I now use used to work, but for some reason it doesn\'t work anymore. W

Answer 1

There is a multibyte split function in PHP, mb_split.

Answer 2

I found out the é was not the character I expected. Apparently there is a difference between né and ńe. I got it working by normalizing the string first.

Answer 3

This is the best solution!:

I've found this nice solution in the PHP manual pages.

preg_split('//u', $str, null, PREG_SPLIT_NO_EMPTY);

It works really fast:

In PHP 5.6.18 it split a 6 MB big text file in a matter of seconds.

Best of all. It doesn't need MultiByte (mb_) support!

Similar answer also here.

Answer 4

For the mb_... functions you should specify the charset encoding.

In your example code these are especially the following two lines:

$strLen = mb_strlen($str, 'UTF-8');
$arr[] = mb_substr($str, $i, $len, 'UTF-8');

The full picture:

function utf8Split($str, $len = 1)
{
  $arr = array();
  $strLen = mb_strlen($str, 'UTF-8');
  for ($i = 0; $i < $strLen; $i++)
  {
    $arr[] = mb_substr($str, $i, $len, 'UTF-8');
  }
  return $arr;
}

Because you're using UTF-8 here. However, if the input is not properly encoded, this won't work "any longer" - just because it has not been designed for something else.

You can alternativly process UTF-8 encoded strings with PCRE regular expressions, for example this will return what you're looking for in less code:

$str = 'Zelf heb ik maar één vraag: wie ben jij?';

$chars = preg_split('/(?!^)(?=.)/u', $str);

Next to preg_split there is also mb_split.

Answer 5

mb_internal_encoding("UTF-8"); 

46 arrays - off 41 arrays

Answer 6

If you not sure about availability of mb_string function library, then use:

Version 1:

function utf8_str_split($str='',$len=1){
    preg_match_all("/./u", $str, $arr);
    $arr = array_chunk($arr[0], $len);
    $arr = array_map('implode', $arr);
    return $arr;
}

Version 2:

function utf8_str_split($str='',$len=1){
    return preg_split('/(?<=\G.{'.$len.'})/u', $str,-1,PREG_SPLIT_NO_EMPTY);
}

Both functions tested in PHP5