Convert all applicable characters to HTML entities (original) (raw)

htmlentities

(PHP 4, PHP 5, PHP 7)

htmlentities — Convert all applicable characters to HTML entities

Description

htmlentities ( string $string [, int $flags = ENT_COMPAT | ENT_HTML401 [, string $encoding = ini_get("default_charset") [, bool $double_encode = TRUE ]]] ) : string

If you want to decode instead (the reverse) you can usehtml_entity_decode().

Parameters

string

The input string.

flags

A bitmask of one or more of the following flags, which specify how to handle quotes, invalid code unit sequences and the used document type. The default isENT_COMPAT | 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_IGNORE Silently discard invalid code unit sequences instead of returning an empty string. Using this flag is discouraged as it» may have security implications.
ENT_SUBSTITUTE Replace invalid code unit sequences with a Unicode Replacement Character U+FFFD (UTF-8) or &#FFFD; (otherwise) instead of returning an empty string.
ENT_DISALLOWED Replace invalid code points for the given document type with a Unicode Replacement Character U+FFFD (UTF-8) or &#FFFD; (otherwise) instead of leaving them as is. This may be useful, for instance, to ensure the well-formedness of XML documents with embedded external content.
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

An optional argument defining the encoding used when converting characters.

If omitted, the default value of the encoding varies depending on the PHP version in use. In PHP 5.6 and later, thedefault_charset configuration option is used as the default value. PHP 5.4 and 5.5 will useUTF-8 as the default. Earlier versions of PHP useISO-8859-1.

Although this argument is technically optional, you are highly encouraged to specify the correct value for your code if you are using PHP 5.5 or earlier, or if your default_charset configuration option may be set incorrectly for the given input.

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() andsetlocale()), in this order. Not recommended.

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

double_encode

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

Return Values

Returns the encoded string.

If the input string contains an invalid code unit sequence within the given encoding an empty string will be returned, unless either the ENT_IGNORE or**ENT_SUBSTITUTE** flags are set.

Changelog

Version Description
5.6.0 The default value for the encoding parameter was changed to be the value of thedefault_charset configuration option.
5.4.0 The default value for the encoding parameter was changed to UTF-8.
5.4.0 The constants ENT_SUBSTITUTE, ENT_DISALLOWED,ENT_HTML401, ENT_XML1,ENT_XHTML and ENT_HTML5 were added.
5.3.0 The constant ENT_IGNORE was added.
5.2.3 The double_encode parameter was added.

Examples

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($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"); ?>

See Also