Last updated: Fri, 09 May 2008

htmlspecialchars

(PHP 4, PHP 5)

htmlspecialchars — 特殊文字を HTML エンティティに変換する

説明

string htmlspecialchars ( string $string [, int $quote_style [, string $charset [, bool $double_encode ]]] )

文字の中には HTML において特殊な意味を持つものがあり、それらの本来の値を表示したければ HTML の表現形式に変換してやらなければなりません。この関数は、これらの変換を行った結果の文字列を返します。これは、日常的な Web プログラミングにおいて最も有用な変換を行います。全ての HTML 文字エンティティを変換する必要がある場合には、代わりに htmlentities() を使用してください。

この関数は、掲示板やゲストブックなどでユーザが書きこんだテキストから HTML のマークアップ用文字を取り除く場合に有用です。

変換対象となる文字は以下の通りです。

'&' (アンパサンド) は '&' になります。
ENT_NOQUOTES が設定されていない場合、 '"' (ダブルクォート) は '"'になります。
ENT_QUOTES が設定されている場合のみ、 ''' (シングルクオート) は '''になります。
'<' (小なり) は '<' になります。
'>' (大なり) は '>' になります。

パラメータ

string

変換される文字列。

quote_style

オプションの 2 番目の引数 quote_style は、シングルおよびダブルクオートされた文字をどのように扱うかを指定します。デフォルトの ENT_COMPAT は下位互換性のためのモードで、ダブルクオートは変換しますがシングルクオートは変換しません。 ENT_QUOTES が設定されている場合は、シングルクオートとダブルクオートを共に変換します。 ENT_NOQUOTES が設定されている場合は、シングルクオートとダブルクオートは共に変換されません。

charset

変換に使用される文字セットを指定します。デフォルトの文字セットは、ISO-8859-1 です。

PHP 4.3.0 以降では、以下の文字セットがサポートされます。

**サポートされる文字セット**
文字セット	エイリアス	説明
ISO-8859-1	ISO8859-1	西欧、Latin-1
ISO-8859-15	ISO8859-15	西欧、Latin-9 。Latin-1(ISO-8859-1) に欠けているユーロ記号やフランス・フィンランドの文字を追加したもの。
UTF-8		ASCII 互換のマルチバイト 8 ビット Unicode 。
cp866	ibm866, 866	DOS 固有のキリル文字セット。 4.3.2 以降でサポートされます。
cp1251	Windows-1251, win-1251, 1251	Windows 固有のキリル文字セット。 4.3.2 以降でサポートされます。
cp1252	Windows-1252, 1252	西欧のための Windows 固有の文字セット。
KOI8-R	koi8-ru, koi8r	ロシア語。4.3.2 以降でサポートされます。
BIG5	950	繁体字中国語。主に台湾で使用されます。
GB2312	936	簡体字中国語。国の標準文字セットです。
BIG5-HKSCS		Big5 に香港の拡張を含めたもの。繁体字中国語。
Shift_JIS	SJIS, 932	日本語。
EUC-JP	EUCJP	日本語。

注意: それ以外の文字セットは理解できず、かわりに ISO-8859-1 が使用されます。

double_encode

double_encode をオフにすると、PHP は既存の html エンティティをエンコードしません。デフォルトでは、既存のエンティティも含めてすべてを変換します。

返り値

変換後の文字列を返します。

変更履歴

バージョン	説明
5.2.3	`double_encode` パラメータが追加されました。
4.1.0	`charset` パラメータが追加されました。

例

例1 htmlspecialchars() の例


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

注意

注意: この関数は上記のあげたもの以外に関しては一切の変換を行わないことに注意してください。すべての変換を行うには htmlentities() を参照してください。

参考

implode

htmlspecialchars_decode

Last updated: Fri, 09 May 2008

add a note User Contributed Notes
htmlspecialchars

php dot net at orakio dot net
10-Apr-2008 11:26


I was recently exploring some code when I saw this being used to make data safe for "SQL".



This function should not be used to make data SQL safe (although to prevent phishing it is perfectly good).



Here is an example of how NOT to use this function:



<?php

$username = htmlspecialchars(trim("$_POST[username]"));



$uniqueuser = $realm_db->query("SELECT `login` FROM `accounts` WHERE `login` = '$username'");

?>



(Only other check on $_POST['username'] is to make sure it isn't empty which it is after trim on a white space only name)



The problem here is that it is left to default which allows single quote marks which are used in the sql query. Turning on magic quotes might fix it but you should not rely on magic quotes, in fact you should never use it and fix the code instead. There are also problems with \ not being escaped. Even if magic quotes were used there would be the problem of allowing usernames longer than the limit and having some really weird usernames given they are to be used outside of html, this just provide a front end for registering to another system using mysql. Of course using it on the output wouldn;t cause that problem.



Another way to make something of a fix would be to use ENT_QUOTE or do:



<?php

$uniqueuser = $realm_db->query('SELECT `login` FROM `accounts` WHERE `login` = "'.$username.'";');

?>



Eitherway none of these solutions are good practice and are not entirely unflawed. This function should simply never be used in such a fashion.



I hope this will prevent newbies using this function incorrectly (as they apparently do).

treyh
09-Apr-2008 11:41


Here is a function that wraps htmlspecialchars and makes it work for xml.



function xmlspecialchars($text) {

   return str_replace('&#039;', '&apos;', htmlspecialchars($text, ENT_QUOTES));

}

crestfresh at gmail dot com
18-Feb-2008 07:02


Re ish1301's jsspecialchars() function: use json_encode() instead.

ish1301 at gmail doooot com
20-Nov-2007 02:56


used this function for making a variable javascript compatible



<?php

function jsspecialchars( $string = '') {

    $string = preg_replace("/\r*\n/","\\n",$string);

    $string = preg_replace("/\//","\\\/",$string);

    $string = preg_replace("/\"/","\\\"",$string);

    $string = preg_replace("/'/"," ",$string);

    return $string;

}

?>

hope this may help those embedding php in javascripts

drew at august-harper dot com
22-Aug-2007 09:21


:// Escapes strings to be included in javascript

:function jsspecialchars($s) {

:    return preg_replace('/([^ :!#$%@()*+,-.\x30-\x5b\x5d-\x7e])/e',

:        "'\\x'.(ord('\\1')<16? '0': '').dechex(ord('\\1'))",$s);

:}



This function DOES NOT produce correct output in PHP5. Any strings containing a ” will be improperly escaped to \x5c, when it should be \x22.



I am not very good with regular expressions, so this is my solution to the problem.

//this is a workaround for jsspecialchars!

function ord2($s) {

if (strlen($s) == 2) {

return ord(substr($s,1,1));

} else {

return ord($s);

}

}

function JS_SpecialChars($s) {

return preg_replace(’/([^ !#$%@()*+,.\x30\x5b\x5d-\x7e])/e’,

”’\\x’.(ord2(’\\1’)&lt;16? ‘0’: ’’).dechex(ord2(’\\1’))”,$s);

}



I am sure that there is a better solution, but I can’t figure one out. This approach will probably also fix any other characters that end up being improperly escaped.

solar-energy
16-Jun-2007 03:21


also see function "urlencode()", useful for passing text with ampersand and other special chars through url



(i.e. the text is encoded as if sent from form using GET method)



e.g.



<?php

echo "<a href='foo.php?text=".urlencode("foo?&bar!")."'>link</a>";

?>



produces



<a href='foo.php?text=foo%3F%26bar%21'>link</a>



and if the link is followed, the $_GET["text"] in foo.php will contain "foo?&bar!"

galvao at galvao dot eti dot br
19-May-2007 06:19


There's a tiny error on alex-0 at hotmail dot co dot uk example:



The line:



$new = htmlspecialchars($_POST[message], ENT_QUOTES);



Should be written as:



$new = htmlspecialchars($_POST['message'], ENT_QUOTES);



Regards,

terminatorul at gmail dot com
27-Apr-2007 10:04


To html-encode Unicode characters that may not be part of your document character set (given in the META tag of your page), and so can not be output directly into your document source, you need to use mb_encode_numericentity(). Pay attention to it's conversion map argument.

frank at codedor dot be
16-Jan-2007 01:25


If you seem to have a problem with rendering dynamic RSS files from a database - try using htmlspecialchars() or htmlentities() on the text you are rendering. 



Since XML and RSS is very strict about what is allowed inside nodes, you need to make sure everything is "A-OK" according to XML standards ...



Especially if the database you're pulling data from is fi. Latin-Swedish encoding, which seems to be the standard setting for MySQL databases.

alex-0 at hotmail dot co dot uk
23-Dec-2006 01:09


You can also use variables.

This is handy when working with forms to clear out an malicious html



<?php

$new = htmlspecialchars($_POST[message], ENT_QUOTES);

echo $new;

?>

MacIsaac
12-Apr-2006 01:05


<?php



// Escapes strings to be included in javascript

function jsspecialchars($s) {

    return preg_replace('/([^ !#$%@()*+,-.\x30-\x5b\x5d-\x7e])/e',

        "'\\x'.(ord('\\1')<16? '0': '').dechex(ord('\\1'))",$s);

}



?>



<script>

var some_variable = '<?= jsspecialchars($_GET['some_variable']) ?>';

</script>

richard at mf2fm dot com
03-Mar-2006 01:06


I had a script which detected swearing and wanted to make sure that words such as 'f &uuml; c k' didn't slip through the system.



After using htmlentities(), the following line converts most extended alphabet characters back to the standard alphabet so you can spot such problems..



$text=eregi_replace("&([a-z])[a-z0-9]{3,};", "\\\\1", $text);



This changes, for example, '&uuml;' into 'u' and '&szlig' into 's'.  Sadly it also converts '&pound;' and '&para;' into 'p' so it's not perfect but does solve a lot of the problems

mikiwoz at yahoo dot co dot uk
06-Oct-2005 02:40


I am not sure, maybe I'm missing something, but I have found something interesting:

I've been working on a project, where I had to use htmlspecialchars (for opbvious reasons). I olso needed to de-code the encoded string. What I have done was almost a copy and paste from php.net:

$trans=get_html_translation_table(HTML_SPECIALCHARS, ENT_QUOTES);

$trans=array_flip($trans);

$string=strtr($encoded, $trans);

(it looked a bit different in my code, but the idea is clear)

I couldn't get the apostrophe sign de-coded, and I needed it for the <A> tags. After an hour or so of debuging, I decided do print_r($trans). What I got was:

...

[&#39;] => '

...

BUT the apostrophe was encoded to $#039; -> note the zero.

I don't suppose it's a bug, but it definetely IS a potential pitfall, watch out for this one.

Luiz Miguel Axcar (lmaxcar at yahoo dot com dot br)
01-Sep-2005 06:16


Hello,



If you are getting trouble to SGDB write/read HTML data, try to use this:



<?php



//from html_entity_decode() manual page

function unhtmlentities ($string) {

   $trans_tbl =get_html_translation_table (HTML_ENTITIES );

   $trans_tbl =array_flip ($trans_tbl );

   return strtr ($string ,$trans_tbl );

}



//read from db

$content = stripslashes (htmlspecialchars ($field['content']));



//write to db

$content = unhtmlentities (addslashes (trim ($_POST['content'])));



//make sure result of function get_magic_quotes_gpc () == 0, you can get strange slashes in your content adding slashes twice



//better to do this using addslashes

$content = (! get_magic_quotes_gpc ()) ? addslashes ($content) : $content;



?>

jspalletta at gmail dot com
12-Jul-2005 05:37


I have found that this regular expression is sufficient for making sure that existing character entities show after htmlspecialchars() replaces _all_ occurrences of & with the &amp; entity.



<?php

// Note: hsc is an abbreviation of htmlspecialchars

function hscFixed($str)

{

    return preg_replace("/&amp;(#[0-9]+|[a-z]+);/i", "&$1;", htmlspecialchars($str));

}

?>



The only flaw I can think of is if you have text of the vein; "&[word];", that is not meant to be a character but rather uses the ampersand and semicolon in their traditional grammatical denotations.  However I think this is highly unlikely to occur (among other reasons, the fact that anyone with enough grammatical inclination to use them as such probably won't leave out the space between the ampersand and the word).

25-Jun-2005 08:44


You can't use htmlspecialchars to create RSS feeds, since it expands ampersands.You need to use something like this:

$content = preg_replace(array('/</', '/>/', '/"/'), array('&lt;', '&gt;', '&quot;'), $content);

palrich at gmail dot com
16-May-2005 01:29


To Alexander Nofftz and urbanheroes:

It's not an IE problem.  There is no &apos; in HTML.  So it's only a problem if someone else does render this as an apostraphe on an HTML page.

paul dot l at aon dot at
09-May-2005 09:50


function reverse_htmlentities($mixed)

{

    $htmltable = get_html_translation_table(HTML_ENTITIES);

    foreach($htmltable as $key => $value)

    {

        $mixed = ereg_replace(addslashes($value),$key,$mixed);

    }

    return $mixed;

}



this is my version of a reversed htmlentities function

thisiswherejunkgoes at gmail dot com
05-May-2005 10:06


If there're any n00bs out there looking for a way to ensure that no html/special chars are getting sent to their databases/put through forms/etc., this has been doing the trick for me (though being at least slightly n00bish, if this won't always work perhaps someone will ammend :-)



function checkforchars ($foo) {



  if ($foo === htmlspecialchars($foo)) {

        return "Valid entry.";

  } else {

        return "Invalid entry.";

  }



}

urbanheroes {at} gmail {dot} com
30-Apr-2005 11:32


In response to the note made by Alexander Nofftz on October 2004, &#39; is used instead of &apos; because IE unfortunately seems to have trouble with the latter.

gt at realvertex.com
28-Apr-2005 09:55


Here is the recursive version that works for both arrays and strings. Doesn't look as elegant as the other recursive versions, because of the input checks.



function HTML_ESC($_input = null, $_esc_keys = false)

{

    if ((null != $_input) && (is_array($_input)))

    {

        foreach($_input as $key => $value)

        {

            if($_esc_keys)

            {

                $_return[htmlspecialchars($key)] = HTML_ESC($value,$_esc_keys);

            }

            else

            {

                $_return[$key] = HTML_ESC($value);

            }

        }

        return $_return;

    }

    elseif(null != $_input)

    {

        return htmlspecialchars($_input);

    }

    else

    {

        return null;

    }

}

took
23-Apr-2005 09:14


The Algo from donwilson at gmail dot com to reverse the action of htmlspecialchars(), edited for germany:



function unhtmlspecialchars( $string )

{

  $string = str_replace ( '&amp;', '&', $string );

  $string = str_replace ( '&#039;', '\'', $string );

  $string = str_replace ( '&quot;', '"', $string );

  $string = str_replace ( '&lt;', '<', $string );

  $string = str_replace ( '&gt;', '>', $string );

  $string = str_replace ( '&uuml;', '�', $string );

  $string = str_replace ( '&Uuml;', '�', $string );

  $string = str_replace ( '&auml;', '�', $string );

  $string = str_replace ( '&Auml;', '�', $string );

  $string = str_replace ( '&ouml;', '�', $string );

  $string = str_replace ( '&Ouml;', '�', $string );    

  return $string;

}

11-Mar-2005 04:22


function htmlspecialchars_array($arr = array()) {

   $rs =  array();

   while(list($key,$val) = each($arr)) {

       if(is_array($val)) {

           $rs[$key] = htmlspecialchars_array($val);

       }

       else {

           $rs[$key] = htmlspecialchars($val, ENT_QUOTES);

       }    

   }

   return $rs;

}

beer UNDRSCR nomaed AT hotmail DOT com
01-Feb-2005 02:46


After inspecting the non-native encoding problem, I noticed that for example, if the encoding is cyrillic, and I write Latin characters that are not part of the encoding (� for example - ae-ligature), the browser will send the real entity, such as &aelig; for this case.

Therefore, the only way I see to display multilingual text that is encoded with entities is by:

<?php

    echo str_replace('&amp;', '&', htmlspecialchars($txt));

?>



The regex for numeric entities will skip the Latin-1 textual entities.

zolinak at zoli dot szathmari dot hu
14-Dec-2004 04:46


A sample function, if anybody want to turn html entities (and special characters) back to simple. (eg: "&egrave;", "<" etc)



function html2specialchars($str){

    $trans_table = array_flip(get_html_translation_table(HTML_ENTITIES));

    return strtr($str, $trans_table);

}

beer UNDRSCR nomaed AT hotmail DOT com
21-Oct-2004 01:03


Quite often, on HTML pages that are not encoded as UTF-8, and people write in not native encoding, some browser (for sure IExplorer) will send the different charset characters using HTML Entities, such as &#1073; for small russian 'b'.

htmlspecialchars() will convert this character to the entity, since it changes all & to &amp; 

What I usually do, is either turn &amp; back to & so the correct characters will appear in the output, or I use some regex to replace all entities of characters back to their original entity:

<?php

    // treat this as pseudo-code, it hasn't been tested...

    $result = preg_replace('/&amp;#(x[a-f0-9]+|[0-9]+);/i', '&#$1;', $source);

?>

Alexander Nofftz
20-Oct-2004 04:41


Why &#39;? The HTML and XML DTDs proposed &apos; for this.

See http://www.w3.org/TR/html/dtds.html#a_dtd_Special_characters



So better use this:



$text = htmlspecialchars($text, ENT_QUOTES);

$text = preg_replace('/&#0*39;/', '&apos;', $text);

mlvanbie at gmail dot com
06-Oct-2004 04:45


The code in the previous note has a bug.  If the original text was `&gt;' then htmlspecialchars will turn it into `&amp;gt;' and the suggested code will turn that into `>'.  The &amp; translation must be last.

donwilson at gmail dot com
25-Sep-2004 09:58


To reverse the action of htmlspecialchars(), use this code:



<?php

    unhtmlspecialchars( $string )

    {

        $string = str_replace ( '&amp;', '&', $string );

        $string = str_replace ( '&#039;', '\'', $string );

        $string = str_replace ( '&quot;', '\"', $string );

        $string = str_replace ( '&lt;', '<', $string );

        $string = str_replace ( '&gt;', '>', $string );

        

        return $string;

    }

?>

thelatesundayshow.com @ nathan (flip it)
02-Sep-2004 11:51


heres a version of the recursive escape function that takes the array byref rather than byval so saves some resources in case of big arrays



function recurse_array_HTML_safe(&$arr) {

    foreach ($arr as $key => $val)

        if (is_array($val))

            recurse_array_HTML_safe($arr[$key]);

        else

            $arr[$key] = htmlspecialchars($val, ENT_QUOTES);

}

moc.xnoitadnuof@310symerej
21-Apr-2004 04:04


Here are some usefull functions.

They will apply || decode, htmlspecialchars || htmlentities recursivly to arrays() || to regular $variables. They also protect agains "double encoding".



<?PHP

function htmlspecialchars_or( $mixed, $quote_style = ENT_QUOTES ){

    return is_array($mixed) ? array_map('htmlspecialchars_or',$mixed, array_fill(0,count($mixed),$quote_style)) : htmlspecialchars(htmlspecialchars_decode($mixed, $quote_style ),$quote_style);

}



function htmlspecialchars_decode( $mixed, $quote_style = ENT_QUOTES ) {

    if(is_array($mixed)){

      return array_map('htmlspecialchars_decode',$mixed, array_fill(0,count($mixed),$quote_style));

  }

  $trans_table = get_html_translation_table( HTML_SPECIALCHARS, $quote_style );

    if( $trans_table["'"] != '&#039;' ) { # some versions of PHP match single quotes to &#39;

        $trans_table["'"] = '&#039;';

    }

    return (strtr($mixed, array_flip($trans_table)));

}



function htmlentities_or($mixed, $quote_style = ENT_QUOTES){

    return is_array($mixed) ? array_map('htmlentities_or',$mixed, array_fill(0,count($mixed),$quote_style)) : htmlentities(htmlentities_decode($mixed, $quote_style ),$quote_style);

}



function htmlentities_decode( $mixed, $quote_style = ENT_QUOTES ) {

  if(is_array($mixed)){

      return array_map('htmlentities_decode',$mixed, array_fill(0,count($mixed),$quote_style));

  }

    $trans_table = get_html_translation_table(HTML_ENTITIES, $quote_style );

    if( $trans_table["'"] != '&#039;' ) { # some versions of PHP match single quotes to &#39;

        $trans_table["'"] = '&#039;';

    }

    return (strtr($mixed, array_flip($trans_table)));

}

?>



These functions are an addition to an earlier post. I would like to give the person some credit but I do not know who it was.



<?  ;llnu=u!eJq dHd?>

Dave Duchene
19-Feb-2004 05:58


Here is a handy function that will escape the contents of a variable, recursing into arrays.



<?php

function escaporize($thing) {

  if (is_array($thing)) {

    $escaped = array();

  

    foreach ($thing as $key => $value) {

      $escaped[$key] = escaporize($value);

    }

    

    return $escaped;

  }

  

  // else

  return htmlspecialchars($thing);

}

?>

mike-php at emerge2 dot com
20-Nov-2003 02:13


Here's a handy function that guards against 'double' encoding:



# Given a string, this function first strips out all html special characters, then

# encodes the string, safely returning an encoded string without double-encoding.

function get_htmlspecialchars( $given, $quote_style = ENT_QUOTES ){

   return htmlspecialchars( html_entity_decode( $given, $quote_style ), $quote_style );

}



# Needed for older versions of PHP that do not have this function built-in.

function html_entity_decode( $given_html, $quote_style = ENT_QUOTES ) {

   $trans_table = get_html_translation_table( HTML_SPECIALCHARS, $quote_style );

   if( $trans_table["'"] != '&#039;' ) { # some versions of PHP match single quotes to &#39;

      $trans_table["'"] = '&#039;';

   }

   return ( strtr( $given_html, array_flip( $trans_table ) ) );

}



Note: I set the default to ENT_QUOTES, as this makes more sense to me than the PHP function's default of ENT_COMPAT.

nospam at somewhere dot com
15-Jun-2003 10:28


most simple function for decoding html-encoded strings:





function htmldecode($encoded) {


    return strtr($encoded,array_flip(get_html_translation_table(HTML_ENTITIES)));


}

dystopia589 at yahoo dot com
13-Mar-2003 07:58


Sorry, part of that code was unnecessary. Here's a more readable version:



function SpecialChars($Security)

{

if (is_array($Security))

{

while(list($key, $val) = each($Security))

{

$Security[$key] = SpecialChars($val);

}

}

else

{

$Security = htmlspecialchars(stripslashes($Security), ENT_QUOTES);

}

return $Security;

}

webmaster at NOSPAM dot onlinegs dot com
28-Jan-2003 10:51


for those of you using V 4.3.0+ you can use html_entity_decode() to decode a string encoded with htmlspecialschars(), this should be faster and easier then using a str_replace or ereg.

_____ at luukku dot com
14-Sep-2002 02:21


People, don't use ereg_replace for the most simple string replacing operations (replacing constant string with another).

Use str_replace.

akira dot yoshi at shrine dot de
15-May-2002 09:15


If you need to htmlspecialchars a jis string, here's a function that does:



function htmlspecialchars_jis($text) {

    $ret="";

    if ($text=="") return "";

    $esc=chr(27);

    $text=$esc."$B".$esc."$B".$text;

    $text=str_replace($esc."(B", $esc."$B", $text);

    $trans=explode($esc."$B", $text);

    $enc=0;

    while (list (, $val) = each ($trans))  {

        if ($enc==0) {

            $val.="";

            if ($val!="") $ret.=htmlspecialchars($val);

            $enc=1;

        } else {

            $val.="";

            if ($val!="") $ret.=$esc."$B".$val.$esc."(B";

            $enc=0;

        };

    }

    return $ret;

};



BTW: I'm very(!) sure that JIS is iso-2022-jp, not iso-2002-jp

juadielon_NOSPAM at hotmail dot com
30-Apr-2002 09:09


I was trying to retrieve information from a database to display it into the browser. However it did not work as I was expecting.  For instance double quotes (��) and single quotes (��) were conflicting in HTML in an INPUT selector.





The first approach to solve this was to use htmlspecialchars to convert special characters to HTML entities to display the input box with its value.





$encode=htmlspecialchars($str, ENT_QUOTES);





However, the result was having HTML entities with a \ (backslash) preceding it (escape characters).  For instance ampersand (&) becomes \&amp; displaying \& and double quotes becomes \&quot; displaying \�





So the final solution was to replace first any \ (backslash) and then ask htmlspecialchars to make the conversion.





[Editor's Note: This is the wrong way to do this. The proper way is to use 





$encoded = htmlspecialchars(stripslashes($str), ENT_QUOTES);


]





$encoded=htmlspecialchars(str_replace('\\', '', $str), ENT_QUOTES);





Try this example to see it your self.





<form action="<?php echo $PHP_SELF; ?>">


<input type="text" name="str" size="20" value="">


<input type="submit" value="Submit">


<br>


<?php


  if (!empty($str)) {


    $encoded=htmlspecialchars(str_replace('\\', '', $str), ENT_QUOTES);


    echo "<br><p>Result: <b>".$encoded."</b>. It should be the same you just typed</p>";


    echo "<p>But source code is transformed to:<b><xmp>".$encoded."</xmp></b></p>";


    // I know, I know <xmp> is deprecated in HTML 4 but was easy to use this time to display result.


  }


?>


</form>





Hope this will helps someone.

akira at kurogane dot net
01-Apr-2002 09:42


Beware of parsing JIS (aka 'iso-2002-jp') text through this function, as this function does not appear to have a sense for multibyte characters and may corrupt some characters. Eg. the japanese comma (the two ascii characters !" as viewed by an ascii client) gets transferred into !&quot; , which transforms the comma into a 'maru' mark and the following characters into garbage. 

Conceivably this could affect other multibyte charsets.

joseph at nextique dot com
20-Feb-2002 01:21


Here is a handy function to htmlalize an array (or scalar) before you hand it off to xml.



function htmlspecialchars_array($arr = array()) {

    $rs =  array();

    while(list($key,$val) = each($arr)) {

        if(is_array($val)) {

            $rs[$key] = htmlspecialchars_array($val);

        }

        else {

            $rs[$key] = htmlspecialchars($val, ENT_QUOTES);

        }    

    }

    return $rs;

}

14-Jul-2001 11:18


If your sending data from one form to another, the data in the textareas and text inputs may need to have htmlspecialchars("form data", ENT_QUOTES) applied, assuming you will ever have quotes or less-than signs or any of those special characters.  Using htmlspecialchars will make the text show up properly in the second form.  The changes are automatically undone whenever the form data is submitted. It does seem a little strange, but it works and my headache is now starting to go away.





AZ

ryan at ryano dot net
29-Jun-2001 03:06


Actually, if you're using >= 4.0.5, this should theoretically be quicker (less overhead anyway):





$text = str_replace(array("&gt;", "&lt;", "&quot;", "&amp;"), array(">", "<", "\"", "&"), $text);

thorax at inforocket dot com
08-Dec-1999 05:26


to convert a document back from this, 


do string replacements in this order:





>   >


<   <


" "


&  &





Doing the last phase first will 


reveal erroneous results.. For example:





'<'  => specialchars() => '&lt;' '&lt;' => convert ampersands => '<' => convert everything else => '<'

add a note

implode

htmlspecialchars_decode

Last updated: Fri, 09 May 2008