PHP: html_entity_decode function - Convert all HTML entities to their applicable characters

Description

string html_entity_decode ( string $string [, int $quote_style [, string $charset ]] )

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

Parameters

string

The input string.

quote_style

The optional second quote_style parameter lets you define what will be done with 'single' and "double" quotes. It takes on one of three constants with the default being ENT_COMPAT:

**Available *`quote_style`* 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.

charset

The ISO-8859-1 character set is used as default for the optional third charset . This defines the character set used in conversion.

Following character sets are supported in PHP 4.3.0 and later.

**Supported charsets**
Charset	Aliases	Description
ISO-8859-1	ISO8859-1	Western European, Latin-1
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. This charset is supported in 4.3.2.
cp1251	Windows-1251, win-1251, 1251	Windows-specific Cyrillic charset. This charset is supported in 4.3.2.
cp1252	Windows-1252, 1252	Windows specific charset for Western European.
KOI8-R	koi8-ru, koi8r	Russian. This charset is supported in 4.3.2.
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, 932	Japanese
EUC-JP	EUCJP	Japanese

Note: Any other character sets are not recognized and ISO-8859-1 will be used instead.

Return Values

Returns the decoded string.

ChangeLog

Version	Description
5.0.0	Support for multi-byte character sets was added.

Examples

Example #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


// For users prior to PHP 4.3.0 you may do this:
function unhtmlentities($string)
{
    // replace numeric entities
    $string = preg_replace('~&#x([0-9a-f]+);~ei', 'chr(hexdec("\\1"))', $string);
    $string = preg_replace('~&#([0-9]+);~e', 'chr("\\1")', $string);
    // replace literal entities
    $trans_tbl = get_html_translation_table(HTML_ENTITIES);
    $trans_tbl = array_flip($trans_tbl);
    return strtr($string, $trans_tbl);
}

$c = unhtmlentities($a);

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

?>

Notes

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

html_entity_decode