Some solution for using national chars and have problem with UTF-8 for example in mail subject. Before you use mb_encode_mimeheader with UTF-8 set mb_internal_encoding('UTF-8').
(PHP 4 >= 4.0.6, PHP 5, PHP 7, PHP 8)
mb_encode_mimeheader — Encode string for MIME header
$string,$charset = null,$transfer_encoding = null,$newline = "\r\n",$indent = 0
Encodes a given string
string by the MIME header encoding scheme.
stringThe string being encoded. Its encoding should be same as mb_internal_encoding().
charset
charset specifies the name of the character set
in which string is represented in. The default value
is determined by the current NLS setting (mbstring.language).
transfer_encoding
transfer_encoding specifies the scheme of MIME
encoding. It should be either "B" (Base64) or
"Q" (Quoted-Printable). Falls back to
"B" if not given.
newline
newline specifies the EOL (end-of-line) marker
with which mb_encode_mimeheader() performs
line-folding (a » RFC term,
the act of breaking a line longer than a certain length into multiple
lines. The length is currently hard-coded to 74 characters).
Falls back to "\r\n" (CRLF) if not given.
indent
Indentation of the first line (number of characters in the header
before string).
A converted version of the string represented in ASCII.
| Version | Description |
|---|---|
| 8.3.0 |
NUL (0) bytes are no longer dropped when encoded
using Quoted-Printable encoding, but encoded as =00.
|
| 8.0.0 |
charset and transfer_encoding
are nullable now.
|
Example #1 mb_encode_mimeheader() example
<?php
$name = "太郎"; // kanji
$mbox = "kru";
$doma = "gtinn.mon";
$addr = '"' . addcslashes(mb_encode_mimeheader($name, "UTF-7", "Q"), '"') . '" <' . $mbox . "@" . $doma . ">";
echo $addr;
?>The above example will output:
"=?UTF-7?Q?+WSqQzg-?=" <kru@gtinn.mon>
Note:
This function isn't designed to break lines at higher-level contextual break points (word boundaries, etc.). This behaviour may clutter up the original string with unexpected spaces.
Some solution for using national chars and have problem with UTF-8 for example in mail subject. Before you use mb_encode_mimeheader with UTF-8 set mb_internal_encoding('UTF-8').True, function is broken (PHP5.1, encoding from UTF-8 with pl_PL charset). Below is about 15% faster version of proposed _mb_mime_encode. Also it has header more like othe mb_* functions and doesn't trigger any errors/warnings/notices.
<?php
function mb_mime_header($string, $encoding=null, $linefeed="\r\n") {
if(!$encoding) $encoding = mb_internal_encoding();
$encoded = '';
while($length = mb_strlen($string)) {
$encoded .= "=?$encoding?B?"
. base64_encode(mb_substr($string,0,24,$encoding))
. "?=$linefeed";
$string = mb_substr($string,24,$length,$encoding);
}
return $encoded;
}
?>Read this FIRST: http://bugs.php.net/bug.php?id=23192 because mb_encode_mimeheaders is BUGGY!
a work around for the multibyte broken error for too long subjects for ISO-2022-JP:
$pos=0;
$split=36; // after 36 single bytes characters, if then comes MB, it is broken
while ($pos<mb_strlen($string,$encoding))
{
$output=mb_strimwidth($string,$pos,$split,"",$encoding);
$pos+=mb_strlen($output,$encoding);
$_string.=(($_string)?' ':'').mb_encode_mimeheader($output,$encoding);
}
$string=$_string;
is not the best, but it worksI could not find a PHP function to MIME encode the name for a n email address.
Input = "Karl Müller<kmueller@gmx.de>"
Output = "Karl%20M%FCller<kmueller@gmx.de>"
I wrote it on my own:
<?php
// required to encode names in email addresses
// replace " " with "%20"
// replace "ü" with "%FC"
// replace "%" with "%25" etc....
// Use "%" as Delimiter for MIME
// Use "=" as Delimiter for Quoted Printable
// Input string must be UTF8 encoded
public static function EncodeMime($Text, $Delimiter)
{
$Text = utf8_decode($Text);
$Len = strlen($Text);
$Out = "";
for ($i=0; $i<$Len; $i++)
{
$Chr = substr($Text, $i, 1);
$Asc = ord($Chr);
if ($Asc > 0x255) // Unicode not allowed
{
$Out .= "?";
}
else if ($Chr == " " || $Chr == $Delimiter || $Asc > 127)
{
$Out .= $Delimiter . strtoupper(bin2hex($Chr));
}
else $Out .= $Chr;
}
return $Out;
}
?>mb_encode_mimeheader() depends on correct mbstring.internal_encoding setting. It tries to convert $str from internal encoding to $charset. If you ignore mbstring internal encoding, function might encode strings incorrectly even when $str character set matches $charsetMy first post was around 2003, and still the mb_mime_header is broken. It is *NOT* usable with longer subjects, and mostly unusable with anything else than japanese.
iwakura at junx dot org is also not working for me, it produces also some gargabe.
I updated my old function (the one I posted 2003) and I tested it with overlong subjects in UTF-8, ISO-2022-JP (japanese), GB2312 (simplified chinese) and EUC-KR (korean) and I got readable results in thunderbird, mail.app, outlook, etc.
<?php
function _mb_mime_encode($string, $encoding)
{
$pos = 0;
// after 36 single bytes characters if then comes MB, it is broken
// but I trimmed it down to 24, to stay 100% < 76 chars per line
$split = 24;
while ($pos < mb_strlen($string, $encoding))
{
$output = mb_strimwidth($string, $pos, $split, "", $encoding);
$pos += mb_strlen($output, $encoding);
$_string_encoded = "=?".$encoding."?B?".base64_encode($output)."?=";
if ($_string)
$_string .= "\r\n";
$_string .= $_string_encoded;
}
$string = $_string;
return $string;
}
?>If mb_ version doesn't work for you in MIME-B mode:
function encode_mimeheader($string, $charset=null, $linefeed="\r\n") {
if (!$charset)
$charset = mb_internal_encoding();
$start = "=?$charset?B?";
$end = "?=";
$encoded = '';
/* Each line must have length <= 75, including $start and $end */
$length = 75 - strlen($start) - strlen($end);
/* Average multi-byte ratio */
$ratio = mb_strlen($string, $charset) / strlen($string);
/* Base64 has a 4:3 ratio */
$magic = $avglength = floor(3 * $length * $ratio / 4);
for ($i=0; $i <= mb_strlen($string, $charset); $i+=$magic) {
$magic = $avglength;
$offset = 0;
/* Recalculate magic for each line to be 100% sure */
do {
$magic -= $offset;
$chunk = mb_substr($string, $i, $magic, $charset);
$chunk = base64_encode($chunk);
$offset++;
} while (strlen($chunk) > $length);
if ($chunk)
$encoded .= ' '.$start.$chunk.$end.$linefeed;
}
/* Chomp the first space and the last linefeed */
$encoded = substr($encoded, 1, -strlen($linefeed));
return $encoded;
}In countries where there's non-us ASCII, it's a very good example, for sending mail:
mb_internal_encoding('iso-8859-2');
setlocale(LC_CTYPE, 'hu_HU');
function encode($str,$charset){
$str=mb_encode_mimeheader(trim($str),$charset, 'Q', "\n\t");
return $str;
}
print encode('the text with spec. chars: ő Ű Ő ű, ?','iso-8859-2');
It creates a 7bit stringi think mb_encode_mimeheader still have bug. here is sample code:
function mb_encode_mimeheader2($string, $encoding = "ISO-2022-JP") {
$string_array = array();
$pos = 0;
$row = 0;
$mode = 0;
while ($pos < mb_strlen($string)) {
$word = mb_strimwidth($string, $pos, 1);
if (!$word) {
$word = mb_strimwidth($string, $pos, 2);
}
if (mb_ereg_match("[ -~]", $word)) { // ascii
if ($mode != 1) {
$row++;
$mode = 1;
$string_array[$row] = NULL;
}
} else { // multibyte
if ($mode != 2) {
$row++;
$mode = 2;
$string_array[$row] = NULL;
}
}
$string_array[$row] .= $word;
$pos++;
}
//echo "<pre>";
//print_r($string_array);
//echo "</pre>";
foreach ($string_array as $key => $value) {
$value = mb_convert_encoding($value, $encoding);
$string_array[$key] = mb_encode_mimeheader($value, $encoding);
}
//echo "<pre>";
//print_r($string_array);
//echo "</pre>";
return implode("", $string_array);
}
is not the best, but it worksAt least for Q encoding, this function is unsafe and does not encode correctly. Raw characters which appear as RFC2047 sequences are simply left as is.
Ex:
mb_encode_mimeheader( '=?iso-8859-1?q?this=20is=20some=20text?=' );
returns '=?iso-8859-1?q?this=20is=20some=20text?='
The exact same string, which is obviously not the encoding for the source string. That is, mb_encode_mimeheader does not do any type of escaping.
That is, the following condition is not always true:
mb_decode_mimeheader( mb_encode_mimeheader( $text ) ) == $text