(PHP 4 >= 4.3.0, PHP 5)
html_entity_decode — Convert all HTML entities to their applicable characters
html_entity_decode() is the opposite of htmlentities() in that it converts all HTML entities to their applicable characters from string .
The input string.
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:
| 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. |
The ISO-8859-1 character set is used as default for the optional third charset . This defines the character set used in conversion.
PHP 4.3.0 及其后续版本支持如下字符集。
| 字符集 | 别名 | 描述 |
|---|---|---|
| ISO-8859-1 | ISO8859-1 | 西欧，Latin-1 |
| ISO-8859-15 | ISO8859-15 | 西欧，Latin-9。增加了 Latin-1（ISO-8859-1）中缺少的欧元符号、法国及芬兰字母。 |
| UTF-8 | ASCII 兼容多字节 8-bit Unicode。 | |
| cp866 | ibm866, 866 | DOS-特有的 Cyrillic 字母字符集。PHP 4.3.2 开始支持该字符集。 |
| cp1251 | Windows-1251, win-1251, 1251 | Windows-特有的 Cyrillic 字母字符集。PHP 4.3.2 开始支持该字符集。 |
| cp1252 | Windows-1252, 1252 | Windows 对于西欧特有的字符集。 |
| KOI8-R | koi8-ru, koi8r | 俄文。PHP 4.3.2 开始支持该字符集。 |
| BIG5 | 950 | 繁体中文，主要用于中国台湾。 |
| GB2312 | 936 | 简体中文，国际标准字符集。 |
| BIG5-HKSCS | 繁体中文，Big5 的延伸，主要用于香港。 | |
| Shift_JIS | SJIS, 932 | 日文。 |
| EUC-JP | EUCJP | 日文。 |
Note: ISO-8859-1 将代替任何其它无法识别的字符集。
Returns the decoded string.
| 版本 | 说明 |
|---|---|
| 5.0.0 | Support for multi-byte character sets was added. |
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 "walk" the <b>dog</b> 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
?>
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.