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.
Like htmlspecialchars(), the optional second quote_style 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:
Table 1. Available quote_style constants
|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.|
Support for the optional quote parameter was added in PHP 4.0.3.
Like htmlspecialchars(), it takes an optional third argument charset which defines character set used in conversion. Support for this argument was added in PHP 4.1.0. Presently, the ISO-8859-1 character set is used as the default.
Following character sets are supported in PHP 4.3.0 and later.
Table 2. Supported charsets
|ISO-8859-1||ISO8859-1||Western European, Latin-1|
|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. This charset is supported in 4.3.2.|
|cp1251||Windows-1251, win-1251, 1251||Windows-specific Cyrillic charset. This charset is supported in 4.3.2.|
|cp1252||Windows-1252, 1252||Windows specific charset for Western European.|
|KOI8-R||koi8-ru, koi8r||Russian. This charset is supported in 4.3.2.|
|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.|
Note: Any other character sets are not recognized and ISO-8859-1 will be used instead.
If you're wanting to decode instead (the reverse) you can use html_entity_decode().