can't assign value to variable inside recursive function - php

Question

I'm trying to create a XML file dynamically trough php, reading DIRS and FILES on a specific directory on my ftp.
So far so god, here's the code:
<?php
$path = ".";
$dir_handle = #opendir($path) or die("Unable to open $path");
function list_dir($dir_handle,$path)
{
while (false !== ($file = readdir($dir_handle))) {
$dir =$path.'/'.$file;
$link =$path.'/';
if(is_dir($dir) && $file != '.' && $file !='..' )
{
$handle = #opendir($dir) or die("unable to open file $file");
$xmlString .= '<' . $file . '>';
list_dir($handle, $dir);
$xmlString .= '</' . $file . '>';
}
elseif($file != '.' && $file !='..' && $file !='ftpteste.php')
{
$xmlString .= '<IMAGE>';
$xmlString .= '<PHOTO>' . $link . '' . $file . '</PHOTO>';
$xmlString .= '</IMAGE>';
}
}
closedir($dir_handle);
}
$xmlString ='<XML>';
list_dir($dir_handle,$path);
$xmlString .="</XML>";
$strXMLhead = '<?xml version="1.0" encoding="UTF-8" ?>';
$xmlString = $strXMLhead . "\n" . $xmlString;
$xmlLoc = "../../interiores/xml/content.xml";
$fileXML = fopen($xmlLoc, "w+") or die("Can't open XML file");
if(!fwrite($fileXML, pack("CCC",0xef,0xbb,0xbf)))
{
print "Error Saving File";
}
else
{
fwrite($fileXML, $xmlString);
print "XML file saved";
}
fclose($fileXML);
?>
The problem is that i'm getting no output on $XmlString running inside the function. If i use Print instead joining the strings it's fine, it does the job. But i need it to be in a variable in order to save to file.
Saving to file it's ok.
It should output something like:
<XML>
<$DIR NAME>
<IMAGE>
<PHOTO>$FILE_NAME</PHOTO>
</IMAGE>
</$DIR NAME>
</XML>
Can anyone help me with this?
thanks in advance,
artur

Answer 1

I think you should take a look at the DomDocument object. It provides an easy way to create a document with nodes (like an xml document). You will be able to avoid your problem with that.

Answer 2

Return the XML you're building from list_dir().
function list_dir($dir_handle,$path)
{
...
$xmlString .= list_dir($handle, $dir);
...
return $xmlString;
}
$xmlString = '<XML>' . list_dir($dir_handle,$path) . '</XML>';