(PHP 4, PHP 5)
htmlentities — Convert all applicable characters to HTML entities
This function is identical to htmlspecialchars() in all ways, except with htmlentities(), all characters which have HTML character entity equivalents are translated into these entities.
If you're wanting to decode instead (the reverse) you can use html_entity_decode().
The input string.
Like htmlspecialchars(), the optional second flags 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, optionally combined with a fourth ENT_IGNORE (since PHP 5.3.0):
| 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_IGNORE | Silently discard invalid code unit sequences instead of returning an empty string. Added in PHP 5.3.0. This is provided for backwards compatibility; avoid using it as it may have security implications. |
Like htmlspecialchars(), it takes an optional third argument charset which defines character set used in conversion. Presently, the ISO-8859-1 character set is used as the default.
以下字符集设置从 PHP 4.3.0 版本开始被支持。
| 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。增加欧元符号，法语和芬兰语字母在 Latin-1(ISO-8859-1) 中缺失。 |
| UTF-8 | ASCII 兼容的多字节 8 位 Unicode。 | |
| cp866 | ibm866, 866 | DOS 特有的西里尔编码。本字符集在 4.3.2 版本中得到支持。 |
| cp1251 | Windows-1251, win-1251, 1251 | Windows 特有的西里尔编码。本字符集在 4.3.2 版本中得到支持。 |
| cp1252 | Windows-1252, 1252 | Windows 特有的西欧编码。 |
| KOI8-R | koi8-ru, koi8r | 俄语。本字符集在 4.3.2 版本中得到支持。 |
| BIG5 | 950 | 繁体中文，主要用于中国台湾省。 |
| GB2312 | 936 | 简体中文，中国国家标准字符集。 |
| BIG5-HKSCS | 繁体中文，附带香港扩展的 Big5 字符集。 | |
| Shift_JIS | SJIS, 932 | 日语 |
| EUC-JP | EUCJP | 日语 |
Note: 其他字符集没有认可。可以使用 ISO-8859-1 来替代。
When double_encode is turned off PHP will not encode existing html entities. The default is to convert everything.
Returns the encoded string.
| 版本 | 说明 |
|---|---|
| 5.3.0 | The constant ENT_IGNORE was added. |
| 5.2.3 | The double_encode parameter was added. |
| 4.1.0 | The charset parameter was added. |
| 4.0.3 | The flags parameter was added. |
Example #1 A htmlentities() example
<?php
$str = "A 'quote' is <b>bold</b>";
// Outputs: A 'quote' is <b>bold</b>
echo htmlentities($str);
// Outputs: A 'quote' is <b>bold</b>
echo htmlentities($str, ENT_QUOTES);
?>
Example #2 Usage of ENT_IGNORE
<?php
$str = "\x8F!!!";
// Outputs an empty string
echo htmlentities($str, ENT_QUOTES, "UTF-8");
// Outputs "!!!"
echo htmlentities($str, ENT_QUOTES | ENT_IGNORE, "UTF-8");
?>