PHP 8.3.4 Released!

chunk_split

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

chunk_splitSplit a string into smaller chunks

Description

chunk_split(string $string, int $length = 76, string $separator = "\r\n"): string

Can be used to split a string into smaller chunks which is useful for e.g. converting base64_encode() output to match RFC 2045 semantics. It inserts separator every length characters.

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
// format $data using RFC 2045 semantics
$new_string = chunk_split(base64_encode($data));
?>

See Also

add a note

User Contributed Notes 20 notes

up
21
vijit at mail dot ru
8 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
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24
qeremy [atta] gmail [dotta] com
12 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
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10
chris AT w3style.co DOT uk
17 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.
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6
chris at ocproducts dot com
6 years ago
The description of the function is slightly inaccurate. A trailing $end is also added.
up
9
mv@NOSPAM
20 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
?>
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5
kevin @t hyguard,com
18 years ago
Not quite completely obvious, but...

you can un_chunk_split() by:

$long_str = str_replace( "\r\n", "", $chunked_str );
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3
hansvane at yahoo dot com dot ar
17 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
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3
Anonymous
10 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.
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4
neos at blizzz dot ru
15 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
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3
Royce
15 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;
}
?>
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3
xamine at gmail dot com
17 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.

?>
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3
belal dot nabeh at gmail dot com
13 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;
}
?>
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3
mark [at] d0gz [dot] net
16 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.
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2
harish at thespitbox dot net
18 years ago
another way to group thousands in a number, which is much simpler, is built into PHP :)

www.php.net/number_format
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3
dampee at earthlink dot net
14 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;
}
?>
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2
Danilo
20 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
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-2
Kevin
18 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;
}
?>
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-4
tim at weird spots in my crotch dot com
15 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;
}
?>
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-4
phpkid
18 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;
}
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-9
Peter from dezzignz.com
13 years ago
chunk_split() is not multibyte safe. If you ever run into needing the function that is multibyte safe, here you go:

<?php

function mbStringToArray ($str) {
if (empty(
$str)) return false;
$len = mb_strlen($str);
$array = array();
for (
$i = 0; $i < $len; $i++) {
$array[] = mb_substr($str, $i, 1);
}
return
$array;
}

function
mb_chunk_split($str, $len, $glue) {
if (empty(
$str)) return false;
$array = mbStringToArray ($str);
$n = 0;
$new = '';
foreach (
$array as $char) {
if (
$n < $len) $new .= $char;
elseif (
$n == $len) {
$new .= $glue . $char;
$n = 0;
}
$n++;
}
return
$new;
}

?>
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