字符串函数
PHP Manual

htmlentities

(PHP 4, PHP 5)

htmlentitiesConvert all applicable characters to HTML entities

说明

string htmlentities ( string $string [, int $flags = ENT_COMPAT [, string $charset [, bool $double_encode = true ]]] )

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().

参数

string

The input string.

flags

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):

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_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.

charset

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。

支持的字符集列表
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。

double_encode

When double_encode is turned off PHP will not encode existing html entities. The default is to convert everything.

返回值

Returns the encoded string.

更新日志

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.

范例

Example #1 A htmlentities() example

<?php
$str 
"A 'quote' is <b>bold</b>";

// Outputs: A 'quote' is &lt;b&gt;bold&lt;/b&gt;
echo htmlentities($str);

// Outputs: A &#039;quote&#039; is &lt;b&gt;bold&lt;/b&gt;
echo htmlentities($strENT_QUOTES);
?>

Example #2 Usage of ENT_IGNORE

<?php
$str 
"\x8F!!!";

// Outputs an empty string
echo htmlentities($strENT_QUOTES"UTF-8");

// Outputs "!!!"
echo htmlentities($strENT_QUOTES ENT_IGNORE"UTF-8");
?>

参见


字符串函数
PHP Manual