Splitting string by fixed length

Question

I am looking for ways to split a string of a unicode alpha-numeric type to fixed lenghts. for example:

    992000199821376John Smith          20070603

and the array should look like this:

Array (
 [0] => 99,
 [1] => 2,
 [2] => 00019982,
 [3] => 1376,
 [4] => "John Smith",
 [5] => 20070603
) 

array data will be split like this:

    Array[0] - Account type - must be 2 characters long,
    Array[1] - Account status - must be 1 character long,
    Array[2] - Account ID - must be 8 characters long,
    Array[3] - Account settings - must be 4 characters long,
    Array[4] - User Name - must be 20 characters long,
    Array[5] - Join Date - must be 8 characters long.

Tillo

Adding a tag gives your question better visibility. – Gallo

not possible to do in unicode (only for ascii). ever. See my answer. – Marston

Answer 1

Or if you want to avoid preg:

$string = '992000199821376John Smith          20070603';
$intervals = array(2, 1, 8, 4, 20, 8);

$start = 0;
$parts = array();

foreach ($intervals as $i)
{
   $parts[] = mb_substr($string, $start, $i);

   $start += $i;
}

Lebron

Using intervals makes it a lot more maintainable. +1 for this solution. – Vaulting

Sorry, doesn't work. Splits by code units in case of unicode, not characters. – Marston

How about $parts[] = mb_substr($string, $start, $i, mb_detect_encoding($string)); ? – Lebron

@jonnyynnoj: I don't think that using mb_detect_encoding here is reliable. Also one should count grapheme clusters, not codepoints. – Melidamelilot

Answer 2

    $s = '992000199821376Николай Шмидт       20070603';

    if (preg_match('~(.{2})(.{1})(.{8})(.{4})(.{20})(.{8})~u', $s, $match))
    {
        list (, $type, $status, $id, $settings, $name, $date) = $match;
    }

Manufacture

Answer 3

Using the substr function would do this quite easily.

$accountDetails = "992000199821376John Smith          20070603";
$accountArray = array(substr($accountDetails,0,2),substr($accountDetails,2,1),substr($accountDetails,3,8),substr($accountDetails,11,4),substr($accountDetails,15,20),substr($accountDetails,35,8));

Should do the trick, other than that regular expressions (as suggested by akond) is probably the way to go (and more flexible). (Figured this was still valid as an alternate option).

Grandnephew

Answer 4

It is not possible to split a unicode string in a way you ask for.

Not possible without making the parts invalid. Some code points have no way of standing out, for example: שׁ is 2 code points (and 4 bytes in UTF-8 and UTF-16) and you cannot split it because it is undefined.

When you work with unicode, "character" is a very slippery term. There are code points, glyphs, etc. See more at http://www.utf8everywhere.org, the part on "length of a string"

Marston

+1. Unicode is great for some things, but complicates string handling tremendously. (Are you sure it's "not possible" though? Perhaps only "very difficult"?) – Memorize

Yes, ghoti, what is asked is not possible. I thought I explained why, didn't I? – Marston