(PHP 3, PHP 4 , PHP 5)

htmlspecialchars --  Convert special characters to HTML entities


string htmlspecialchars ( string string [, int quote_style [, string charset]])

Certain characters have special significance in HTML, and should be represented by HTML entities if they are to preserve their meanings. This function returns a string with some of these conversions made; the translations made are those most useful for everyday web programming. If you require all HTML character entities to be translated, use htmlentities() instead.

This function is useful in preventing user-supplied text from containing HTML markup, such as in a message board or guest book application. The optional second argument, quote_style, tells the function what to do with single and double quote characters. The default mode, ENT_COMPAT, is the backwards compatible mode which only translates the double-quote character and leaves the single-quote untranslated. If ENT_QUOTES is set, both single and double quotes are translated and if ENT_NOQUOTES is set neither single nor double quotes are translated.

The translations performed are:

Esempio 1. htmlspecialchars() example

= htmlspecialchars("<a href='test'>Test</a>", ENT_QUOTES);
$new; // &lt;a href=&#039;test&#039;&gt;Test&lt;/a&gt;

Note that this function does not translate anything beyond what is listed above. For full entity translation, see htmlentities(). Support for the optional second argument was added in PHP 3.0.17 and PHP 4.0.3.

The third argument charset defines character set used in conversion. The default character set is ISO-8859-1. Support for this third argument was added in PHP 4.1.0.

Elenco dei set di caratteri supportati dal PHP 4.3.0 e successivi.

Tabella 1. set di caratteri supportati

Set di caratteriAliasDescrizione
ISO-8859-1ISO8859-1 Western European, Latin-1
ISO-8859-15ISO8859-15 Western European, Latin-9. Con in più il simbolo dell'Euro e i caratteri francesi e finnici mancanti in Latin-1(ISO-8859-1).
UTF-8  Set ASCII compatibile con il set multi-byte Unicode su 8-bit.
cp866ibm866, 866 Set di caratteri cirillico specifico del Dos. Supportato dalla 4.3.2.
cp1251Windows-1251, win-1251, 1251 Set di caratteri cirillico specifico di Windows, Supportato dalla 4.3.2.
cp1252Windows-1252, 1252 Set di caratteri specifico di Windows per l'Europa occidentale.
KOI8-Rkoi8-ru, koi8r Russo. Supportato dalla 4.3.2.
BIG5950 Cinese tradizionale, usato principalmente a Taiwan.
GB2312936 Cinese semplificato, set di caratteri nazionale standard.
BIG5-HKSCS  Big5 con estensioni per Hong Kong, cinese tradizionale.
Shift_JISSJIS, 932 Giapponese.
EUC-JPEUCJP Giapponese.

Nota: Ogni altro set di caratteri non è riconosciuto e sarà sostituito con con il set ISO-8859-1.

See also get_html_translation_table(), strip_tags(), htmlentities(), and nl2br().