chunk_split

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

chunk_split将字符串分割成小块

说明

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

使用此函数将字符串分割成小块非常有用。例如将 base64_encode() 的输出转换成符合 RFC 2045 语义的字符串。它会在每 length 个字符后边插入 separator

参数

string

要分割的字符。

length

分割的尺寸。

separator

行尾序列符号。

返回值

返回分割后的字符。

范例

Example #1 chunk_split() 例子

<?php
// 使用 RFC 2045 语义格式化 $data
$new_string chunk_split(base64_encode($data));
?>

参见

User Contributed Notes

chris at ocproducts dot com 24-Apr-2017 07:48
The description of the function is slightly inaccurate. A trailing $end is also added.
vijit at mail dot ru 23-Feb-2016 06:22
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?

й

рус
ски
й
Anonymous 19-Feb-2014 01:57
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.
qeremy [atta] gmail [dotta] com 28-Feb-2012 03:35
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;
}

$str = "Yar?m kilo ?ay, yar?m kilo ?eker";
echo
chunk_split($str, 4) ."\n";
echo
chunk_split_unicode($str, 4);
?>

Yar?
?m k
ilo
?ay
, ya
r?m
 kil
o ?
eker

Yar?
m ki
lo ?
ay,
yar?
m ki
lo ?
eker
belal dot nabeh at gmail dot com 10-Aug-2010 08:02
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;
}
?>
Peter from dezzignz.com 05-Apr-2010 04:30
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;
}

?>
dampee at earthlink dot net 20-Nov-2009 09:10
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;
}
?>
tim at weird spots in my crotch dot com 08-May-2008 02:29
@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;
}
?>
neos at blizzz dot ru 03-May-2008 11:38
"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 16-Apr-2008 12:31
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;
}
?>
mark [at] d0gz [dot] net 10-Apr-2007 10:12
When using ssmtp for simple command line mailing:

$mail_to = "[email protected]";
$msg = "this would be an actual base64_encoded gzip msg";
$date = date(r);
$mail  = "X-FROM: [email protected] \n";
$mail .= "X-TO: ".$mail_to. " \n";
$mail .= "To: ".$mail_to. " \n";
$mail .= "Date: $date \n";
$mail .= "From: [email protected] \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.
hansvane at yahoo dot com dot ar 21-Jan-2007 10:06
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
chris AT w3style.co DOT uk 14-Aug-2006 12:32
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.
xamine at gmail dot com 04-Jun-2006 11:06
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 03-Oct-2005 07:08
Not quite completely obvious, but...

you can un_chunk_split() by:

$long_str = str_replace( "\r\n", "", $chunked_str );
harish at thespitbox dot net 30-Jul-2005 05:45
another way to group thousands in a number, which is much simpler, is built into PHP :)

www.php.net/number_format
Kevin 25-Jun-2005 04:10
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;
}
?>
phpkid 28-May-2005 10:47
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;
}
mv@NOSPAM 24-Jan-2004 07:39
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
?>
Danilo 10-Dec-2003 02:51
>> 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