HTMLSPECIALCHARS(3)							 1						       HTMLSPECIALCHARS(3)

htmlspecialchars - Convert special characters to HTML entities

SYNOPSIS

       string htmlspecialchars (string	$string, [int  $flags = ENT_COMPAT | ENT_HTML401], [string  $encoding = ini_get("default_charset")], [bool
       $double_encode = true])

DESCRIPTION

	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 these conversions made. If you require all input substrings that have associated named entities to be
       translated, use htmlentities(3) instead.

	If the input string passed to this function and the final document share the same character set, this function is  sufficient  to  prepare
       input  for  inclusion in most contexts of an HTML document. If, however, the input can represent characters that are not coded in the final
       document character set and you wish to retain those characters (as numeric or named  entities),	both  this  function  and  htmlentities(3)
       (which  only  encodes  substrings  that	have named entity equivalents) may be insufficient. You may have to use mb_encode_numericentity(3)
       instead.

	The translations performed are:

	      o '&' (ampersand) becomes '&'

	      o '"' (double quote) becomes '"' when
		ENT_NOQUOTES is not set.

	      o "'" (single quote) becomes ''' (or ') only when
		ENT_QUOTES is set.

	      o '<' (less than) becomes '&lt;'

	      o '>' (greater than) becomes '&gt;'

PARAMETERS

	      o $string
		- The string being converted.

	      o $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 is ENT_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  uncon- |
	      | 	      | verted. 					  |
	      | 	      | 						  |
	      | 	      | 						  |
	      |  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  Uni- |
	      | 	      | code  Replacement  Character  U+FFFD  (UTF-8)  or |
	      | 	      | &#FFFD; (otherwise) instead of returning an empty |
	      | 	      | string. 					  |
	      | 	      | 						  |
	      | 	      | 						  |
	      |ENT_DISALLOWED | 						  |
	      | 	      | 						  |
	      | 	      |  Replace  invalid code points for the given docu- |
	      | 	      | ment 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.		  |
	      | 	      | 						  |
	      +---------------+---------------------------------------------------+
	      o $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, the default_charset configuration option is used as the default
		value. PHP 5.4 and 5.5 will use UTF-8 as the default. Earlier versions of PHP use ISO-8859-1.  Although this argument  is  techni-
		cally  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.  For the	purposes  of  this  function,  the
		encodings  ISO-8859-1,	ISO-8859-15,  UTF-8,  cp866,  cp1251,  cp1252, and KOI8-R are effectively equivalent, provided the $string
		itself is valid for the encoding, as the characters affected by htmlspecialchars(3) occupy the same  positions	in  all  of  these
		encodings.  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 let- |   |
	      | 	   | ters     missing	  in	  Latin-1 |   |
	      | 	   | (ISO-8859-1).			  |   |
	      | 	   |					  |   |
	      |   UTF-8    |					  |   |
	      | 	   |					  |   |
	      | 	   |					  |   |
	      | 	   | |T{				  |   |
	      | 	   |  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  West- |   |
	      | 	   | ern European.			  |   |
	      | 	   |					  |   |
	      |  KOI8-R    |					  |   |
	      | 	   |					  |   |
	      | 	   |		koi8-ru, koi8r		  |   |
	      | 	   |					  |   |
	      | 	   |		   Russian.		  |   |
	      | 	   |					  |   |
	      |   BIG5	   |					  |   |
	      | 	   |					  |   |
	      | 	   |		     950		  |   |
	      | 	   |					  |   |
	      | 	   |  Traditional Chinese, mainly used in |   |
	      | 	   | Taiwan.				  |   |
	      | 	   |					  |   |
	      |  GB2312    |					  |   |
	      | 	   |					  |   |
	      | 	   |		     936		  |   |
	      | 	   |					  |   |
	      | 	   |  Simplified Chinese, national  stan- |   |
	      | 	   | dard character set.		  |   |
	      | 	   |					  |   |
	      |BIG5-HKSCS  |					  |   |
	      | 	   |					  |   |
	      | 	   |					  |   |
	      | 	   | |T{				  |   |
	      | 	   |  Big5  with  Hong	Kong  extensions, |   |
	      | 	   | Traditional Chinese.		  |   |
	      | 	   |					  |   |
	      | Shift_JIS  |					  |   |
	      | 	   |					  |   |
	      | 	   |	  SJIS, SJIS-win, cp932, 932	  |   |
	      | 	   |					  |   |
	      | 	   |		   Japanese		  |   |
	      | 	   |					  |   |
	      |  EUC-JP    |					  |   |
	      | 	   |					  |   |
	      | 	   |	       EUCJP, eucJP-win 	  |   |
	      | 	   |					  |   |
	      | 	   |		   Japanese		  |   |
	      | 	   |					  |   |
	      | MacRoman   |					  |   |
	      | 	   |					  |   |
	      | 	   |					  |   |
	      | 	   |  |T{				  |   |
	      | 	   |   Charset that was used by Mac OS.   |   |
	      | 	   |					  |   |
	      | 	   |					  |   |
	      |    ''	   |					  |   |
	      | 	   |					  |   |
	      | 	   |					  |   |
	      | 	   | |T{				  |   |
	      | 	   |  An empty string activates detection |   |
	      | 	   | from  script  encoding  (Zend multi- |   |
	      | 	   | byte), default_charset  and  current |   |
	      | 	   | locale  (see nl_langinfo(3) and set- |   |
	      | 	   | locale(3)), in this order. Not  rec- |   |
	      | 	   | ommended.				  |   |
	      | 	   |					  |   |
	      +------------+--------------------------------------+---+
	      Note

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

	      o $double_encode
		- When $double_encode is turned off PHP will not encode existing html entities, the default is to convert everything.

RETURN VALUES

	The converted 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	the |
       |	| default_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

	      htmlspecialchars(3) example

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

NOTES

       Note

	       Note that this function does not translate anything beyond what is listed above. For full entity translation, see htmlentities(3).

SEE ALSO

       get_html_translation_table(3), htmlspecialchars_decode(3), strip_tags(3), htmlentities(3), nl2br(3).

PHP Documentation Group 												       HTMLSPECIALCHARS(3)