PHP String Reference[1] Example Convert the predefined characters '<' (less than) and '>' (greater than) to HTML entities: 
 <?php$str = 'This is some <b>bold</b> text.';echo htmlspecialchars($str);
 ?> The HTML output of the code above will be (View Source): 
 <!DOCTYPE html><html>
 <body>
 This is some <b>bold</b> text.
 </body>
 </html>
 
 The browser output of the code above will be: 
 
 This is some <b>bold</b> text. Run example »[2] Definition and Usage The htmlspecialchars() function converts some predefined characters to HTML entities. The predefined characters are: & (ampersand) becomes &
 ' (double quote) becomes "
 ' (single quote) becomes '
 < (less than) becomes <
 > (greater than) becomes >
 Tip: To convert special HTML entities back to characters, 
 use the 
 htmlspecialchars_decode()[3] 
 function. Syntax 
 
 htmlspecialchars(string,flags,character-set,double_encode)
 
 Parameter
 Description
 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 stringIf 
 the string contains invalid encoding, it will return an empty 
 string, unless either the ENT_IGNORE or ENT_SUBSTITUTE flags are set
 PHP Version:
 4+
 Changelog:
 The default value for the character-set parameter was changed 
 to UTF-8 in PHP 5ENT_SUBSTITUTE, ENT_DISALLOWED, ENT_HTML401, ENT_HTML5, 
 ENT_XML1 and ENT_XHTML were added in PHP 5.4ENT_IGNORE was added in 
 PHP 5.3The double_encode parameter was added in PHP 5.2.3The character-set parameter was added in PHP 4.1
 More Examples Example 1 Convert some predefined characters to HTML entities: 
 <?php
 $str = 'Jane & 'Tarzan'';
 echo htmlspecialchars($str, ENT_COMPAT); // Will only convert double quotes
 echo '<br>';
 echo htmlspecialchars($str, ENT_QUOTES); // Converts double and single quotes
 echo '<br>';
 echo htmlspecialchars($str, ENT_NOQUOTES); // Does not convert any quotes
 ?> The HTML output of the code above will be (View Source): 
 <!DOCTYPE html><html>
 <body>
 Jane & 'Tarzan'<br>
 Jane & 'Tarzan'<br>
 Jane & 'Tarzan'
 </body>
 </html>
 
 The browser output of the code above will be: 
 
 Jane & 'Tarzan'
 Jane & 'Tarzan'
 Jane & 'Tarzan'
 Run example »[4] Example 2 Convert double quotes to HTML entities: 
 <?php
 $str = 'I love 'PHP'.';echo htmlspecialchars($str, ENT_QUOTES); 
 // Converts double and single quotes
 ?> The HTML output of the code above will be (View Source): 
 <!DOCTYPE html><html>
 <body>
 I love "PHP".
 </body>
 </html>
 
 The browser output of the code above will be: 
 
 I love 'PHP'. Run example »[5] PHP String Reference[6] Thank You For Helping Us! Your message has been sent to W3Schools. Close [X] References^ PHP String Reference (www.w3schools.com)^ Run example » (www.w3schools.com)^ htmlspecialchars_decode() (www.w3schools.com)^ Run example » (www.w3schools.com)^ Run example » (www.w3schools.com)^ PHP String Reference (www.w3schools.com)