Which php function converts some special characters into character entities

❮ PHP String Reference

Example

Convert some characters to HTML entities:

$str = 'Go to w3schools.com';
echo htmlentities($str);
?>

The HTML output of the code above will be (View Source):

<a href="https://www.w3schools.com">Go to w3schools.com</a>

The browser output of the code above will be:

Go to w3schools.com

Try it Yourself »


Definition and Usage

The htmlentities() function converts characters to HTML entities.

Tip: To convert HTML entities back to characters, use the html_entity_decode() function.

Tip: Use the get_html_translation_table() function to return the translation table used by htmlentities().


Syntax

htmlentities(string,flags,character-set,double_encode)

Parameter Values

ParameterDescription
string Required. Specifies the string to convert
flags Optional. Specifies how to handle quotes, invalid encoding and the used document type.

The available quote styles are:

  • ENT_COMPAT - Default. Encodes only double quotes
  • ENT_QUOTES - Encodes double and single quotes
  • ENT_NOQUOTES - Does not encode any quotes

Invalid encoding:

  • ENT_IGNORE - Ignores invalid encoding instead of having the function return an empty string. Should be avoided, as it may have security implications.
  • ENT_SUBSTITUTE - Replaces invalid encoding for a specified character set with a Unicode Replacement Character U+FFFD (UTF-8) or &#FFFD; instead of returning an empty string.
  • ENT_DISALLOWED - Replaces code points that are invalid in the specified doctype with a Unicode Replacement Character U+FFFD (UTF-8) or &#FFFD;

Additional flags for specifying the used doctype:

  • ENT_HTML401 - Default. Handle code as HTML 4.01
  • ENT_HTML5 - Handle code as HTML 5
  • ENT_XML1 - Handle code as XML 1
  • ENT_XHTML - Handle code as XHTML
character-set Optional. A string that specifies which character-set to use.

Allowed values are:

  • UTF-8 - Default. ASCII compatible multi-byte 8-bit Unicode
  • ISO-8859-1 - Western European
  • ISO-8859-15 - Western European (adds the Euro sign + French and Finnish letters missing in ISO-8859-1)
  • cp866 - DOS-specific Cyrillic charset
  • cp1251 - Windows-specific Cyrillic charset
  • cp1252 - Windows specific charset for Western European
  • KOI8-R - Russian
  • BIG5 - Traditional Chinese, mainly used in Taiwan
  • GB2312 - Simplified Chinese, national standard character set
  • BIG5-HKSCS - Big5 with Hong Kong extensions
  • Shift_JIS - Japanese
  • EUC-JP - Japanese
  • MacRoman - Character-set that was used by Mac OS

Note: Unrecognized character-sets will be ignored and replaced by ISO-8859-1 in versions prior to PHP 5.4. As of PHP 5.4, it will be ignored an replaced by UTF-8.

double_encode Optional. A boolean value that specifies whether to encode existing html entities or not.
  • TRUE - Default. Will convert everything
  • FALSE - Will not encode existing html entities


Technical Details

Return Value:Returns the converted string. However, if the string parameter contains invalid encoding, it will return an empty string, unless either the ENT_IGNORE or ENT_SUBSTITUTE flags are set
PHP Version:4+
Changelog:PHP 5.6 - Changed the default value for the character-set parameter to the value of the default charset (in configuration).
PHP 5.4 - Changed the default value for the character-set parameter to UTF-8.
PHP 5.4 - Added ENT_SUBSTITUTE, ENT_DISALLOWED, ENT_HTML401, ENT_HTML5, ENT_XML1 and ENT_XHTML
PHP 5.3 - Added ENT_IGNORE constant.
PHP 5.2.3 - Added the double_encode parameter.
PHP 4.1 - Added the character-set parameter.

More Examples

Example

Convert some characters to HTML entities:

$str = "Albert Einstein said: 'E=MC²'";
echo htmlentities($str, ENT_COMPAT); // Will only convert double quotes
echo "
";
echo htmlentities($str, ENT_QUOTES); // Converts double and single quotes
echo "
";
echo htmlentities($str, ENT_NOQUOTES); // Does not convert any quotes
?>

The HTML output of the code above will be (View Source):

Albert Einstein said: 'E=MC²'

Albert Einstein said: 'E=MC²'

Albert Einstein said: 'E=MC²'

The browser output of the code above will be:

Albert Einstein said: 'E=MC²'
Albert Einstein said: 'E=MC²'
Albert Einstein said: 'E=MC²'

Try it Yourself »

Example

Convert some characters to HTML entities using the Western European character-set:

$str = "My name is Øyvind Åsane. I'm Norwegian.";
echo htmlentities($str, ENT_QUOTES, "UTF-8"); // Will only convert double quotes (not single quotes), and uses the character-set Western European
?>

The HTML output of the code above will be (View Source):




My name is Øyvind Åsane. I'm Norwegian.

The browser output of the code above will be:

My name is Øyvind Åsane. I'm Norwegian.

Try it Yourself »


❮ PHP String Reference


Which is the PHP function that converts certain characters to HTML entities?

The htmlentities() function converts characters to HTML entities. Tip: To convert HTML entities back to characters, use the html_entity_decode() function. Tip: Use the get_html_translation_table() function to return the translation table used by htmlentities().

What is the use of HTML entities () function in PHP?

htmlentities() Function: The htmlentities() function is an inbuilt function in PHP that is used to transform all characters which are applicable to HTML entities. This function converts all characters that are applicable to HTML entities.

What is the difference between Addslashes () and HTML entities () in terms of functionality?

They are different tools for different purposes. mysqli_real_escape_string makes data safe for inserting into MySQL (but parametrized queries are better). addslashes assumes everything is 8bit. mysql_real_escape_string takes the character encoding into account when doing its encoding.

What is HTML encoding in PHP?

Encoding for HTML means converting reserved characters into HTML character entities. HTML character entities are written as &code; , where "code" is an abbreviation or a number to represent each character.