[WSG] Encoding test page

[Keryx webb]

Hello all!

I month or so ago Lachlan and I had a discussion concerning how browsers 
interpret different ways of specifying charsets.

I've written a small test-page, located at:
http://ne.keryx.se/xhtmldemo/encoding_tests.php

(That server is primarily intended for the use of my students and I'd encourage 
you to set up a page of your own if you intend to use this more than once or twice.)

According to my tests Firefox *will* use the charset specified in the 
http-header over the one in the XML-prologue if a page is sent as 
application/xhtml+xml. (Or more exactly, regardless whether the page is sent as 
text/html or application/xhtml+xml.) As will Opera.

The meta-tag mostly seems to go ignored, at least for pages sent over http. 
There might be some issues with the servers default http-header settings or with 
 the browsers cache that I have not tested. The results differ somewhat when I 
test on my laptop (apache on Win) and on the public server (apache on Linux), 
but the apache response headers are exactly the same for both!


Lars Gunther

P.S. My script is attached.

Make sure there are no whitespace before the opening php-tag
as that will make it impossible to send http-headers.


Title: Encoding demo

* @license Creative Commons Share Alike
*/

define('ISO','iso-8859-1');
define('UTF','UTF-8');

// Set headers
$httpHeaderChar = 'Not set';
if ( isset($_POST['httpHeaderChar']) ) {
    if (strcmp($_POST['httpHeaderChar'],'ISO') == 0 ) {
        $httpHeaderChar = ISO;
    } elseif (strcmp($_POST['httpHeaderChar'],'UTF') == 0 ) {
        $httpHeaderChar = UTF;
    }
}
$httpHeaderHtml = 'text/html'; // default
if ( isset($_POST['httpHeaderType']) && strcmp($_POST['httpHeaderType'],'xhtml') == 0 ) {
    $httpHeaderHtml = 'application/xhtml+xml';
}


$headerString = $httpHeaderHtml;
$headerString.= ( $httpHeaderChar != 'Not set' ) ? '; charset='.$httpHeaderChar : '';
header('Content-type: '.$headerString);

ob_start();

// Set XML-prologue
$xmlPrologue = 'Not set';
if ( isset($_POST['xmlPrologue']) ) {
    if (strcmp($_POST['xmlPrologue'],'ISO') == 0 ) {
        $xmlPrologue = '<'.'?xml version="1.0" encoding="'.ISO."\"?>\n";
    } else if (strcmp($_POST['xmlPrologue'],'UTF') == 0 ) {
        $xmlPrologue = '<'.'?xml version="1.0" encoding="'.UTF."\"?>\n";
    } else if (strcmp($_POST['xmlPrologue'],'NOCHAR') == 0 ) {
        $xmlPrologue = '<'.'?xml version="1.0" '."?>\n";
    }
}
if ( $xmlPrologue != 'Not set' ) echo $xmlPrologue;

?>




  Test of different ways to specifying the encoding
  
    The next paragraph should read "å, Å, ä, Ä, ö, Ö". But if
    the browser interprets the text using the wrong charset, it will look weird or be squares or question marks.
  
  å, Å, ä, Ä, ö, Ö.
  Current values
  
a.k.a.ISO-8859-1';
echo 'Real encoding'.$realEncoding."\n";
echo 'Http-headers'.$headerString."\n";
echo 'XML-prologue'.htmlspecialchars($xmlPrologue)."\n";
echo 'Meta-tag'.htmlspecialchars($metaString)."\n";
?>
  
  
    
      Specify encoding for the page
      
      Encode page with UTF-8.
      
      Encode page with Latin-1 (default).
    
    
      Set new values for HTTP-header
      
      Set http-header to UTF-8.
      
      Set http-header to Latin-1.
      
      Do not specify charset in http-header (default).
      
      
      Set http-header to text/html (default).
      
      Set http-header to application/xhtml+xml.
    
    
      Set new values for XML-prologue
      
      Set XML prologue to UTF-8.
      
      Set XML prologue to Latin-1.
      
      Do not specify charset in XML-prologue.
      
      Do not include XML-prologue at all (default).
    
    
      Set new values for the meta-tag
      
      Set meta-tag to UTF-8.
      
      Set meta-tag to Latin-1.
      
      Do not set meta-tag at all (default).
    
    
      
    
  
  
  Apache response headers