PHP 8.3.4 Released!

ord

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

ord Konvertiert das erste Byte einer Zeichenkette in einen Wert zwischen 0 und 255

Beschreibung

ord(string $character): int

Interpretiert den ASCII-Wert des ersten Bytes von character als vorzeichenlose Ganzzahl zwischen 0 und 255.

Liegt die Zeichenkette in einer Ein-Byte-Kodierung, wie ASCII, ISO-8859 oder Windows 1252, vor, ist dies gleichwertig zur Rรผckgabe der Position des Zeichens in der Zuordnungstabelle des Zeichensatzes. Allerdings ist zu beachten, dass diese Funktion keine Zeichenkettenkodierung kennt, und insbesondere niemals einen Unicode-Codepoint in einer Multibyte-Kodierung wie UTF-8 oder UTF-16 erkennt.

Die Funktion ist das Gegenstรผck zu chr().

Parameter-Liste

character

Ein Zeichen.

Rรผckgabewerte

Ein Integer zwischen 0 und 255.

Beispiele

Beispiel #1 ord()-Beispiel

<?php
$str
= "\n";
if (
ord($str) == 10) {
echo
"Das erste Zeichen von \$str ist ein Zeilenvorschub.\n";
}
?>

Beispiel #2 Untersuchen der einzelnen Bytes einer UTF-8-Zeichenkette

<?php
declare(encoding='UTF-8');
$str = "๐Ÿ˜";
for (
$pos=0; $pos < strlen($str); $pos ++ ) {
$byte = substr($str, $pos);
echo
'Byte ' . $pos . ' von $str hat den Wert ' . ord($byte) . PHP_EOL;
}
?>

Das oben gezeigte Beispiel erzeugt folgende Ausgabe:


Byte 0 von $str hat den Wert 240
Byte 1 von $str hat den Wert 159
Byte 2 von $str hat den Wert 144
Byte 3 von $str hat den Wert 152

Siehe auch

๏ผ‹add a note

User Contributed Notes 6 notes

up
47
arglanir+phpnet at gmail dot com
11 years ago
As ord() doesn't work with utf-8, and if you do not have access to mb_* functions, the following function will work well:
<?php
function ordutf8($string, &$offset) {
$code = ord(substr($string, $offset,1));
if (
$code >= 128) { //otherwise 0xxxxxxx
if ($code < 224) $bytesnumber = 2; //110xxxxx
else if ($code < 240) $bytesnumber = 3; //1110xxxx
else if ($code < 248) $bytesnumber = 4; //11110xxx
$codetemp = $code - 192 - ($bytesnumber > 2 ? 32 : 0) - ($bytesnumber > 3 ? 16 : 0);
for (
$i = 2; $i <= $bytesnumber; $i++) {
$offset ++;
$code2 = ord(substr($string, $offset, 1)) - 128; //10xxxxxx
$codetemp = $codetemp*64 + $code2;
}
$code = $codetemp;
}
$offset += 1;
if (
$offset >= strlen($string)) $offset = -1;
return
$code;
}
?>
$offset is a reference, as it is not easy to split a utf-8 char-by-char. Useful to iterate on a string:
<?php
$text
= "abcร รชรŸโ‚ฌabc";
$offset = 0;
while (
$offset >= 0) {
echo
$offset.": ".ordutf8($text, $offset)."\n";
}
/* returns:
0: 97
1: 98
2: 99
3: 224
5: 234
7: 223
9: 8364
12: 97
13: 98
14: 99
*/
?>
Feel free to adapt my code to fit your needs.
up
19
rowan dot collins at cwtdigital dot com
10 years ago
Regarding character sets, and whether or not this is "ASCII". Firstly, there is no such thing as "8-bit ASCII", so if it were ASCII it would only ever return integers up to 127. 8-bit ASCII-compatible encodings include the ISO 8859 family of encodings, which map various common characters to the values from 128 to 255. UTF-8 is also designed so that characters representable in 7-bit ASCII are coded the same; byte values higher than 127 in a UTF-8 string represent the beginning of a multi-byte character.

In fact, like most of PHP's string functions, this function isn't doing anything to do with character encoding at all - it is just interpreting a binary byte from a string as an unsigned integer. That is, ord(chr(200)) will always return 200, but what character chr(200) *means* will vary depending on what character encoding it is *interpreted* as part of (e.g. during display).

A technically correct description would be "Returns an integer representation of the first byte of a string, from 0 to 255. For single-byte encodings such as (7-bit) ASCII and the ISO 8859 family, this will correspond to the first character, and will be the position of that character in the encoding's mapping table. For multi-byte encodings, such as UTF-8 or UTF-16, the byte may not represent a complete character."

The link to asciitable.com should also be replaced by one which explains what character encoding it is displaying, as "Extended ASCII" is an ambiguous and misleading name.
up
7
paco at olecode dot com
4 years ago
this function convert UTF-8 string to RTF code string. I am using code of v0rbiz at yahoo dot com, thanks!!!

function cadena_rtf($txt)
{
$result = null;

for ($pos = 0; $pos < mb_strlen($txt); $pos++) {

$char = mb_substr($txt, $pos, 1);

if (!preg_match("/[A-Za-z1-9,.]/", $char)) {
//unicode ord real!!!
$k = mb_convert_encoding($char, 'UCS-2LE', 'UTF-8');
$k1 = ord(substr($k, 0, 1));
$k2 = ord(substr($k, 1, 1));
$ord = $k2 * 256 + $k1;

if ($ord > 255) {
$result .= '\uc1\u' . $ord . '*';
} elseif ($ord > 32768) {
$result .= '\uc1\u' . ($ord - 65535) . '*';
} else {
$result .= "\\'" . dechex($ord);
}
} else {
$result .= $char;
}
}
return $result;
}
up
9
v0rbiz at yahoo dot com
19 years ago
I did not found a unicode/multibyte capable 'ord' function, so...

<?php
function uniord($u) {
$k = mb_convert_encoding($u, 'UCS-2LE', 'UTF-8');
$k1 = ord(substr($k, 0, 1));
$k2 = ord(substr($k, 1, 1));
return
$k2 * 256 + $k1;
}
?>
up
-1
Noname
2 years ago
<?php

declare (encoding='UTF-8');

$animalsstr = '๐Ÿ€๐Ÿ๐Ÿ‚๐Ÿƒ๐Ÿ„๐Ÿ…๐Ÿ†๐Ÿ‡๐Ÿˆ๐Ÿ‰๐ŸŠ๐Ÿ‹๐ŸŒ๐Ÿ๐ŸŽ๐Ÿ๐Ÿ๐Ÿ‘๐Ÿ’๐Ÿ“๐Ÿ”๐Ÿ•๐Ÿ–๐Ÿ—๐Ÿ˜๐Ÿ™'
. '๐Ÿš๐Ÿ›๐Ÿœ๐Ÿ๐Ÿž๐ŸŸ๐Ÿ ๐Ÿก๐Ÿข๐Ÿฃ๐Ÿค๐Ÿฅ๐Ÿฆ๐Ÿง๐Ÿจ๐Ÿฉ๐Ÿช๐Ÿซ๐Ÿฌ๐Ÿญ๐Ÿฎ๐Ÿฏ๐Ÿฐ๐Ÿฑ๐Ÿฒ๐Ÿณ๐Ÿด๐Ÿต'
. '๐Ÿถ๐Ÿท๐Ÿธ๐Ÿน๐Ÿบ๐Ÿป๐Ÿผ๐Ÿฝ๐Ÿพ๐Ÿฟ';

$animals = mb_str_split($animalsstr);
foreach (
$animals as $animal) {
for (
$pos = 0; $pos < strlen($animal); $pos++) {
$byte = substr($animal, $pos);
echo
"Byte $pos of $animal has value " . ord($byte) . PHP_EOL;
}
}

?>
up
-3
Anonymous
2 years ago
For anyone who's looking to convert full strings to map and back it's pretty simple but takes some getting used to...the code below saves an hour of scrounging codes for beginners like myself.

function var2map($a) {
$b='';
$c=strlen($a);
for($i=0; $i<$c; ++$i) {
$d=ord(substr($a,$i,1));
if($d<10) {
$e='00'.$d;
} else {
if($d<100) {
$e='0'.$d;
} else {
$e=$d;
}
}
if($b=='') {
$b=$e;
} else {
$b=$b.$e;
}
}
return $b;
}

function map2var($a) {
$b='';
$c=strlen($a) / 3;
for($i=0; $i<$c; ++$i) {
$d=chr(substr($a,$i*3,3));
if($b=='') {
$b=$d;
} else {
$b=$b.$d;
}
}
return $b;
}
To Top