htmlspecialchars

Description

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:

'&' (ampersand) becomes '&'
'"' (double quote) becomes '"' when ENT_NOQUOTES is not set.
''' (single quote) becomes ''' only when ENT_QUOTES is set.
'<' (less than) becomes '<'
'>' (greater than) becomes '>'

例子 1. htmlspecialchars() example


<?php
$new = htmlspecialchars("<a href='test'>Test</a>", ENT_QUOTES);
echo $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.

PHP 4.3.0 及其後續版本支援如下字集。

表格 1. 已支援字集

字集	別名	描述
ISO-8859-1	ISO8859-1	西歐，Latin-1
ISO-8859-15	ISO8859-15	西歐，Latin-9。增加了 Latin-1（ISO-8859-1）中缺少的歐元符號、法國及芬蘭字母。
UTF-8		ASCII 相容多位元組 8-bit Unicode。
cp866	ibm866, 866	DOS-特有的 Cyrillic 字母字集。PHP 4.3.2 開始支援該字集。
cp1251	Windows-1251, win-1251, 1251	Windows-特有的 Cyrillic 字母字集。PHP 4.3.2 開始支援該字集。
cp1252	Windows-1252, 1252	Windows 對於西歐特有的字集。
KOI8-R	koi8-ru, koi8r	俄文。PHP 4.3.2 開始支援該字集。
BIG5	950	繁體中文，主要用於中國台灣。
GB2312	936	繁體中文，國際標準字集。
BIG5-HKSCS		繁體中文，Big5 的延伸，主要用於香港。
Shift_JIS	SJIS, 932	日文。
EUC-JP	EUCJP	日文。

注: ISO-8859-1 將代替任何其它無法識別的字集。