PHP: chunk_split - Manual

(PHP 4, PHP 5, PHP 7, PHP 8)

chunk_splitSplit a string into smaller chunks

Description

Parameters

string

The string to be chunked.

length

The chunk length.

separator

The line ending sequence.

Return Values

Returns the chunked string.

Examples

Example #1 chunk_split() example

<?php
$data
= 'This is quite a long string, which will get broken up because the line is going to be too long after base64 encoding it.';// format $data using RFC 2045 semantics
$new_string = chunk_split(base64_encode($data));
echo
$new_string, PHP_EOL;
?>

See Also

Found A Problem?

vijit at mail dot ru

10 years ago

As an alternative for  qeremy [atta] gmail [dotta] com
There is much shorter way for binarysafe chunking of multibyte string:

<?php
function word_chunk($str, $len = 76, $end = "\n") {
    $pattern = '~.{1,' . $len . '}~u'; // like "~.{1,76}~u"
    $str = preg_replace($pattern, '$0' . $end, $str);
    return rtrim($str, $end);
}

$str = 'русский';
echo chunk_split($str, 3) ."\n";
echo word_chunk($str, 3) . "\n";
?>

р�
�с
с�
�и
й

рус
ски
й

qeremy [atta] gmail [dotta] com

14 years ago

An alternative for unicode strings;

<?php
function chunk_split_unicode($str, $l = 76, $e = "\r\n") {
    $tmp = array_chunk(
        preg_split("//u", $str, -1, PREG_SPLIT_NO_EMPTY), $l);
    $str = "";
    foreach ($tmp as $t) {
        $str .= join("", $t) . $e;
    }
    return $str;
}

$str = "Yarım kilo çay, yarım kilo şeker";
echo chunk_split($str, 4) ."\n";
echo chunk_split_unicode($str, 4);
?>

Yar�
�m k
ilo 
çay
, ya
rım
 kil
o ş
eker

Yarı
m ki
lo ç
ay, 
yarı
m ki
lo ş
eker

chris AT w3style.co DOT uk

19 years ago

I'm not sure what versions this also occurs in but the output of chunk_split() in PHP 5.0.4 does not match the output in other versions of PHP.

In all versions of PHP I have used, apart from 5.0.4 chunk_split() adds the separator (\r\n) to the end of the string.  But in PHP 5.0.4 this does not happen.  This had a fairly serious impact on a library I maintain so it may also affect others who are not aware of this.

chris at ocproducts dot com

8 years ago

The description of the function is slightly inaccurate. A trailing $end is also added.

mv@NOSPAM

22 years ago

the best way to solve the problem with the last string added by chunk_split() is:

<?php
$string = '1234';
substr(chunk_split($string, 2, ':'), 0, -1);
// will return 12:34
?>

Anonymous

12 years ago

Important note is the maximum line length and the recommended one. The standard says:
"Lines in a message MUST be a maximum of 998 characters excluding the CRLF, but it is RECOMMENDED that lines be limited to 78 characters excluding the CRLF. "

See PHP manual for chunk_split() Which is set to 76 characters long chunk and "\r\n" at the end of line by default.

hansvane at yahoo dot com dot ar

19 years ago

This function is very simple and many other functions make this on PHP 5 and even some ones in 4 the good think about this one is that work on php 3.0.6 and 4 

function split_hjms_chars($xstr, $xlenint, $xlaststr)
{
    $texttoshow = chunk_split($xstr,$xlenint,"\r\n"); 
    $texttoshow  = split("\r\n",$texttoshow);
    $texttoshow = $texttoshow[0].$xlaststr;
    return $texttoshow;
}

// For use 

echo split_hjms_chars("This is your text",6,"...");

// Will return

This i...

It is useful to cut long text on preview lists and if the server it's old.

Hope it helps some one. Hans Svane

neos at blizzz dot ru

17 years ago

"version" of chunk_split for cyrillic characters in UTF-8

public function UTFChunk($Text,$Len = 10,$End = "\r\n")
{
    if(mb_detect_encoding($Text) == "UTF-8")
    {
        return mb_convert_encoding(
                chunk_split(
                    mb_convert_encoding($Text, "KOI8-R","UTF-8"), $Len,$End
                ),
                "UTF-8", "KOI8-R"
            );
    } else
    {
        return chunk_split($Text,$Len,$End);
    }
}

this is example for russian language

Royce

17 years ago

Here's a version of Chunk Split I wrote that will not split html entities. Useful if you need to inject something in html (in my case, <wbr/> tags to allow for long text wrapping).

<?php
function HtmlEntitySafeSplit($html,$size,$delim)
{
  $pos=0;
  for($i=0;$i<strlen($html);$i++)
  {
    if($pos >= $size && !$unsafe)
    {
      $out.=$delim;
      $unsafe=0;
      $pos=0;
    }
    $c=substr($html,$i,1);
    if($c == "&")
      $unsafe=1;
    elseif($c == ";")
      $unsafe=0;
    $out.=$c;
    $pos++;
  }
  return $out;
}
?>

xamine at gmail dot com

19 years ago

In reply to "adrian at zhp dot inet dot pl" digit grouping function:
<?php
    $number = strrev(chunk_split (strrev($number), 3,' '));
    //If $number is '1234567', result is '1 234 567'.
?>

There is a much more simple way of doing this, by using the built-in number_format() function. 

<?php 
   $number = number_format($number,2,"."," ");

   //This will round $number to 2 decimals, use the dot (".")
   //as decimal point, and the space (" ") as thousand sepparator.

?>

kevin @t hyguard,com

20 years ago

Not quite completely obvious, but... 

you can un_chunk_split() by:

$long_str = str_replace( "\r\n", "", $chunked_str );

harish at thespitbox dot net

20 years ago

another way to group thousands in a number, which is much simpler, is built into PHP :)

www.php.net/number_format

mark [at] d0gz [dot] net

18 years ago

When using ssmtp for simple command line mailing:

$mail_to = "destination@emailbox.com";
$msg = "this would be an actual base64_encoded gzip msg";
$date = date(r);
$mail  = "X-FROM: root@sender.org \n";
$mail .= "X-TO: ".$mail_to. " \n";
$mail .= "To: ".$mail_to. " \n";
$mail .= "Date: $date \n";
$mail .= "From: root@sender.org \n";
$mail .= "Subject: lifecheck \n";
$mail .= $msg." \n";
exec("echo '$mail' | /usr/sbin/ssmtp ".$mail_to);

be sure to invoke chunk_split() on your message body - ssmtp becomes unhappy with long lines and will subsequently trash  your message.

dampee at earthlink dot net

16 years ago

I've found this quite useful for simulating various kinds of shuffles with cards.  It is humorous but can imitate multiple deck cuts and other (imperfectly) random events.

<?php
function truffle_shuffle($body, $chunklen = 76, $end = "\r\n")
{
     $chunk = chunk_split($body, $chunklen, "-=blender=-");
     $truffle = explode("-=blender=-",$chunk);
     $shuffle = shuffle($truffle);
     $huknc = implode($end,$shuffle);
     return $huknc;
}
?>

Danilo

22 years ago

>> chunk_split will also add the break _after_ the last occurence.

this should be not the problem 

substr(chunk_split('FF99FF', 2, ':'),0,8);
will return FF:99:FF

belal dot nabeh at gmail dot com

15 years ago

If you are using UTF-8 charset you will face a problem with Arabic language
to solve this problem i used this function

<?php
function chunk_split_($text,$length,$string_end)
{
    $text = iconv("UTF-8","windows-1256",$text);
    $text = str_split($text);
    foreach($text as $val)
    {
        if($a !== $val)
        {
            $a = $val;
            $x = 0;
        }else{
            $a = $val;
            $x++;
        }
        if($x > $length)
        {
            $new_text .= $val.$string_end;
            $x = 0;
        }else
        {
             $new_text .= $val;
        }
        
    }
    $new_text = iconv("windows-1256","UTF-8",$new_text);
    return $new_text;
}
?>

Kevin

20 years ago

To phpkid:

This is a much simpler solution.

<?php
function longWordWrap($string) {
    $string = str_replace("\n", "\n ", $string); // add a space after newline characters, so that 2 words only seperated by \n are not considered as 1 word
    $words = explode(" ", $string); // now split by space
    foreach ($words as $word) {
        $outstring .= chunk_split($word, 12, " ") . " ";
    }
    return $outstring;
}
?>

tim at weird spots in my crotch dot com

17 years ago

@Royce

I think this is better, since you can still use the ampersand in your text:

<?php
function HtmlEntitySafeSplit($html,$size,$delim)
{
  $pos=0;
  for($i=0;$i<strlen($html);$i++)
  {
    if($pos >= $size && !$unsafe)
    {
      $out.=$delim;
      $unsafe=0;
      $pos=0;
    }
    $c=substr($html,$i,1);
    if($c == "&")
      $unsafe=1;
    elseif($c == ";")
      $unsafe=0;
    elseif($c == " ")
      $unsafe=0;
    $out.=$c;
    $pos++;
  }
  return $out;
}
?>

phpkid

20 years ago

Well I have been having issues with a shoutbox I am coding it would keep expanding the <TD> if there were large words in it but I fixed it with this:

function PadString($String){
    $Exploded = explode(" ", $String);
    $Max_Parts = count($Exploded);
    
    $CurArray = 0;
    $OutString = '';
    while($CurArray<=$Max_Parts)
    {
        $Peice_Size = strlen($Exploded[$CurArray]);
        if($Peice_Size>15)
        {
            $OutString .= chunk_split($Exploded[$CurArray], 12, " ");
            $CurArray++;
        } else {
            $OutString .= " ".$Exploded[$CurArray];
            $CurArray++;
        }
    }
    
    return $OutString;
}