How to use htmlentities function

php htmlentities function is used to convert characters into HTML escape characters.

#How to use the htmlentities function?

php htmlentities() function syntax

Function: Convert characters to HTML entities

Syntax:

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

Parameters:

string Required, specifies the string to be converted

flagsOptional. Specifies how to handle quotes, invalid encodings, and which document type to use. Available quote types:

ENT_COMPAT - Default. Only double quotes are encoded.

ENT_QUOTES - Encodes double and single quotes.

ENT_NOQUOTES - Do not encode any quotes.

Invalid encoding: ENT_IGNORE - Ignore invalid encodings instead of having the function return an empty string. This should be avoided as this may have an impact on security.

ENT_SUBSTITUTE - Substitutes an invalid encoding with the specified character with the Unicode substitution character U FFFD (UTF-8) or FFFD; instead of returning an empty string.

ENT_DISALLOWED - Replaces invalid code points in the specified document type with the Unicode replacement character U FFFD (UTF-8) or FFFD;. Additional flags specifying the document type to use:

ENT_HTML401 - Default. Code processed as HTML 4.01.

ENT_HTML5 - Process code as HTML 5. ENT_XML1 - Code processed as XML 1.

ENT_XHTML - Processing code as XHTML.

character-set Optional. A string specifying the character set to be used. Allowed values: UTF-8 - Default. ASCII compatible multi-byte 8-bit Unicode, ISO-8859-1 - Western Europe, ISO-8859-15 - Western Europe (adds French and Finnish letters missing from ISO-8859-1 for Euro symbol), cp866 - DOS-specific Cyrillic characters set, cp1251 - Windows-specific Cyrillic character set, cp1252 - Windows-specific Western European character set, KOI8-R - Russian, BIG5 - Traditional Chinese, mainly used in Taiwan, GB2312 - Simplified Chinese, national standard character set, BIG5-HKSCS - with Hong Kong Extended Big5, Shift_JIS - Japanese, EUC-JP - Japanese, MacRoman - Character set used by Mac operating systems. In versions prior to PHP 5.4, unrecognized character sets will be ignored and replaced by ISO-8859-1. As of PHP 5.4, unrecognized character sets are ignored and replaced by UTF-8.

double_encodeOptional. Boolean value that specifies whether to encode existing HTML entities. TRUE - Default. Each entity will be converted. FALSE - Existing HTML entities will not be encoded.

Description: Convert characters into HTML entities.

php htmlentities() function usage example:

<?php
$str = "Bill& &#39;Steve&#39;";
echo htmlentities($str, ENT_COMPAT); // 只转换双引号
echo "<br>";
echo htmlentities($str, ENT_QUOTES); // 转换双引号和单引号
echo "<br>";
echo htmlentities($str, ENT_NOQUOTES); // 不转换任何引号
?>

Output:

Bill & 'Steve'
Bill & 'Steve'
Bill & 'Steve'

This article is an introduction to the PHP htmlentities function. I hope it will help you if you need Friends help!

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