PHP: get_html_translation_table

Description

array get_html_translation_table ( [int table [, int quote_style]] )

get_html_translation_table() will return the translation table that is used internally for htmlspecialchars() and htmlentities().

There are two new constants (HTML_ENTITIES, HTML_SPECIALCHARS) that allow you to specify the table you want. Default value for table is HTML_SPECIALCHARS. And as in the htmlspecialchars() and htmlentities() functions you can optionally specify the quote_style you are working with. The default is ENT_COMPAT mode. See the description of these modes in htmlspecialchars().

Przykład 1. Translation Table Example


<?php

$trans = get_html_translation_table(HTML_ENTITIES);

$str = "Hallo & <Frau> & Krämer";

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

?>

The $encoded variable will now contain: "Hallo & <Frau> & Krämer".

Another interesting use of this function is to, with help of array_flip(), change the direction of the translation.


<?php

$trans = array_flip($trans);

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

?>

The content of $original would be: "Hallo & <Frau> & Krämer".

User Contributed Notes


Not sure what's going on here but I've run into a problem that others might face as well...



<?php



$translations = array_flip(get_html_translation_table(HTML_ENTITIES,ENT_QUOTES));



?>



returns the single quote ' as being equal to &#39; while



<?php



$translatedString = htmlentities($string,ENT_QUOTES);



?>

returns it as being equal to &#039;



I've had to do a specific string replacement for the time being... Not sure if it's an issue with the function or the array manipulation.



-Pat


If you want to display special HTML entities in a web browser, you can use the following code:



<?

$entities = get_html_translation_table(HTML_ENTITIES);

foreach ($entities as $entity) {

    $new_entities[$entity] = htmlspecialchars($entity);

}

echo "<pre>";

print_r($new_entities);

echo "</pre>";

?>



If you don't, the key name of each element will appear to be the same as the element content itself, making it look mighty stupid. ;)


In XML, you can't assume that the doctype will include the same character entity definitions as HTML. XML authors may require character references instead. The following two functions use get_html_translation_table() to encode data in numeric references. The second, optional argument can be used to substitute a different translation table.



function xmlcharacters($string, $trans='') {

    $trans=(is_array($trans))? $trans:get_html_translation_table(HTML_ENTITIES, ENT_QUOTES);

    foreach ($trans as $k=>$v)

        $trans[$k]= "&#".ord($k).";";

    return strtr($string, $trans);

}

function xml_character_decode($string, $trans='') {

    $trans=(is_array($trans))? $trans:get_html_translation_table(HTML_ENTITIES, ENT_QUOTES);

    foreach ($trans as $k=>$v)

        $trans[$k]= "&#".ord($k).";";

    $trans=array_flip($trans);

    return strtr($string, $trans);

}


Alans version didn't seem to work right. If you're having the same problem consider using this slightly modified version instead:



function unhtmlentities ($string)  {

   $trans_tbl = get_html_translation_table (HTML_ENTITIES);

   $trans_tbl = array_flip ($trans_tbl);

   $ret = strtr ($string, $trans_tbl);

   return preg_replace('/&#(\d+);/me', 

      "chr('\\1')",$ret);

}


If you want to decode all those &#123; symbols as well.... 



function unhtmlentities ($string)  {

    $trans_tbl = get_html_translation_table (HTML_ENTITIES);

    $trans_tbl = array_flip ($trans_tbl);

    $ret = strtr ($string, $trans_tbl);

    return  preg_replace('/\&\#([0-9]+)\;/me', 

        "chr('\\1')",$ret);

}


Caution: This function is implemented separately from htmlentities() and htmlspecialchars() in the PHP source, and hence is quite likely to diverge from these functions.





In particular, in 4.0.2 htmlspecialchars() escapes the single quote character, whereas the translation table returned by this function does not.