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html_entity_decode

(PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8)

html_entity_decodeConvert HTML entities to their corresponding characters

Опис

html_entity_decode(string $string, int $flags = ENT_QUOTES | ENT_SUBSTITUTE | ENT_HTML401, ?string $encoding = null): string

html_entity_decode() is the opposite of htmlentities() in that it converts HTML entities in the string to their corresponding characters.

More precisely, this function decodes all the entities (including all numeric entities) that a) are necessarily valid for the chosen document type — i.e., for XML, this function does not decode named entities that might be defined in some DTD — and b) whose character or characters are in the coded character set associated with the chosen encoding and are permitted in the chosen document type. All other entities are left as is.

Параметри

string

The input string.

flags

A bitmask of one or more of the following flags, which specify how to handle quotes and which document type to use. The default is ENT_QUOTES | ENT_SUBSTITUTE | ENT_HTML401.

Available flags constants
Constant Name Description
ENT_COMPAT Will convert double-quotes and leave single-quotes alone.
ENT_QUOTES Will convert both double and single quotes.
ENT_NOQUOTES Will leave both double and single quotes unconverted.
ENT_SUBSTITUTE Replace invalid code unit sequences with a Unicode Replacement Character U+FFFD (UTF-8) or � (otherwise) instead of returning an empty string.
ENT_HTML401 Handle code as HTML 4.01.
ENT_XML1 Handle code as XML 1.
ENT_XHTML Handle code as XHTML.
ENT_HTML5 Handle code as HTML 5.

encoding

Необов'язковий параметр. Ним вказується кодування, що застосовуватиметься під час перетворення символів.

Якщо пропущено, то параметр encoding отримає значення директиви default_charset.

Хоча технічно цей аргумент є необов'язковим, але рекомендується вказати в коді потрібне значення, оскільки директива default_charset може бути неправильною для заданих вхідних даних.

The following character sets are supported:

Supported charsets
Charset Aliases Description
ISO-8859-1 ISO8859-1 Western European, Latin-1.
ISO-8859-5 ISO8859-5 Little used cyrillic charset (Latin/Cyrillic).
ISO-8859-15 ISO8859-15 Western European, Latin-9. Adds the Euro sign, French and Finnish letters missing in Latin-1 (ISO-8859-1).
UTF-8   ASCII compatible multi-byte 8-bit Unicode.
cp866 ibm866, 866 DOS-specific Cyrillic charset.
cp1251 Windows-1251, win-1251, 1251 Windows-specific Cyrillic charset.
cp1252 Windows-1252, 1252 Windows specific charset for Western European.
KOI8-R koi8-ru, koi8r Russian.
BIG5 950 Traditional Chinese, mainly used in Taiwan.
GB2312 936 Simplified Chinese, national standard character set.
BIG5-HKSCS   Big5 with Hong Kong extensions, Traditional Chinese.
Shift_JIS SJIS, SJIS-win, cp932, 932 Japanese
EUC-JP EUCJP, eucJP-win Japanese
MacRoman   Charset that was used by Mac OS.
''   An empty string activates detection from script encoding (Zend multibyte), default_charset and current locale (see nl_langinfo() and setlocale()), in this order. Not recommended.

Зауваження: Any other character sets are not recognized. The default encoding will be used instead and a warning will be emitted.

Значення, що повертаються

Returns the decoded string.

Журнал змін

Версія Опис
8.1.0 flags changed from ENT_COMPAT to ENT_QUOTES | ENT_SUBSTITUTE | ENT_HTML401.
8.0.0 encoding is nullable now.

Приклади

Приклад #1 Decoding HTML entities

<?php
$orig
= "I'll \"walk\" the <b>dog</b> now";

$a = htmlentities($orig);

$b = html_entity_decode($a);

echo
$a; // I'll &quot;walk&quot; the &lt;b&gt;dog&lt;/b&gt; now

echo $b; // I'll "walk" the <b>dog</b> now
?>

Примітки

Зауваження:

You might wonder why trim(html_entity_decode('&nbsp;')); doesn't reduce the string to an empty string, that's because the '&nbsp;' entity is not ASCII code 32 (which is stripped by trim()) but ASCII code 160 (0xa0) in the default ISO 8859-1 encoding.

Прогляньте також

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User Contributed Notes 5 notes

up
130
Martin
13 years ago
If you need something that converts &#[0-9]+ entities to UTF-8, this is simple and works:

<?php
/* Entity crap. /
$input = "Fovi&#269;";

$output = preg_replace_callback("/(&#[0-9]+;)/", function($m) { return mb_convert_encoding($m[1], "UTF-8", "HTML-ENTITIES"); }, $input);

/* Plain UTF-8. */
echo $output;
?>
up
28
txnull
9 years ago
Use the following to decode all entities:
<?php html_entity_decode($string, ENT_QUOTES | ENT_XML1, 'UTF-8') ?>

I've checked these special entities:
- double quotes (&#34;)
- single quotes (&#39; and &apos;)
- non printable chars (e.g. &#13;)
With other $flags some or all won't be decoded.

It seems that ENT_XML1 and ENT_XHTML are identical when decoding.
up
6
aidan at php dot net
20 years ago
This functionality is now implemented in the PEAR package PHP_Compat.

More information about using this function without upgrading your version of PHP can be found on the below link:

http://pear.php.net/package/PHP_Compat
up
-1
Benjamin
11 years ago
The following function decodes named and numeric HTML entities and works on UTF-8. Requires iconv.

function decodeHtmlEnt($str) {
$ret = html_entity_decode($str, ENT_COMPAT, 'UTF-8');
$p2 = -1;
for(;;) {
$p = strpos($ret, '&#', $p2+1);
if ($p === FALSE)
break;
$p2 = strpos($ret, ';', $p);
if ($p2 === FALSE)
break;

if (substr($ret, $p+2, 1) == 'x')
$char = hexdec(substr($ret, $p+3, $p2-$p-3));
else
$char = intval(substr($ret, $p+2, $p2-$p-2));

//echo "$char\n";
$newchar = iconv(
'UCS-4', 'UTF-8',
chr(($char>>24)&0xFF).chr(($char>>16)&0xFF).chr(($char>>8)&0xFF).chr($char&0xFF)
);
//echo "$newchar<$p<$p2<<\n";
$ret = substr_replace($ret, $newchar, $p, 1+$p2-$p);
$p2 = $p + strlen($newchar);
}
return $ret;
}
up
-3
Daniel A.
6 years ago
I wanted to use this function today and I found the documentation, especially about the flags, not particularly helpful.

Running the code below, for example, failed because the flag I used was the wrong one...

$string = 'Donna&#039;s Bakery';
$title = html_entity_decode($string, ENT_HTML401, 'UTF-8');
echo $title;

The correct flag to use in this case is ENT_QUOTES.

My understanding of the flag to use is the one that would correspond to the expected, converted outcome. So, ENT_QUOTES for a character that would be a single or double quote when converted... and so on.

Please help make the documentation a bit clearer.
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