php xml frustration - whats wrong here?

prometheos

hi,
im trying to get a html/php form to either generate or add to an xml file depending on whether or not that file is already created.

For the file not existing, i have this to create the xml file:

[php]$xml = simplexml_load_file("./xml_files/".$user_id.".xml");

$item = new SimpleXMLElement("<items></items>");
$hi = $item->addChild("item");
$hi->addChild("itemName",$item_n);
$hi->addChild("itemSource",$source);
$item->asXML("./xml_files/".$user_id.".xml");
[/php]this generates the xml when it's executed.


for the case where the file already exists, assuming the first tag is <items> just like the created one in the last example, i have this:
[php]
$xml = simplexml_load_file("./xml_files/".$user_id.".xml");
$item = new SimpleXMLElement($xml->asXML());
$by = $item->addChild("item");
$by->addChild("itemName",$item_n);
$by->addChild("itemSource",$source);
$item->asXML("./xml_files/".$user_id.".xml");
[/php]Both of these work on their own(ie. I remove the xml and the second method for the 1st example, or leave an xml file in the directory and delete the first method).

The problem is when i try to combine them... as i said, the plan was to use either 1 depending on if the xml file already existed or not, so i thought i'd use the 'if (file_exists(file))' method. Here's what i have :
[php]
$filename = "./xml_files/".$user_id.".xml";
if (!file_exists($filename)) {
$xml = simplexml_load_file("./xml_files/".$user_id.".xml");

$item = new SimpleXMLElement("<items></items>");
$hi = $item->addChild("item");
$hi->addChild("itemName",$item_n);
$hi->addChild("itemSource",$source);
$item->asXML("./xml_files/".$user_id.".xml");

}else{

$xml = simplexml_load_file("./xml_files/".$user_id.".xml");
$item = new SimpleXMLElement($xml->asXML());
$by = $item->addChild("item");
$by->addChild("itemName",$item_n);
$by->addChild("itemSource",$source);
$item->asXML("./xml_files/".$user_id.".xml");
}
[/php]Can anyone see why this won't work or offer a suggestion please? ive been at it for hours
cheers

Goodshape

Have you tried using an absolute path for file_exists() ?

if (!file_exists($_SERVER . $filename)) { stuff }

prometheos

hi,
yeah i tried that and it works if theres no xml file already there, but if i go back and submit the form again it overwrites the xml file instead of adding to it?
i dont think it likes my file check
Its like it works with the first block nomatter which it is but never gets to the second block
thanks for your suggestion by the way

prometheos

ok, this call seems to work ...
[php]if (!file_exists($_SERVER.$filename)) {}[/php] call
but this one doesnt? [php]if (file_exists($_SERVER.$filename)){}[/php]
even if i use the not one first and put else or else if, it doesnt work
any ideas?

seamus

Check out the notes in the manual on this function:
http://ie2.php.net/manual/en/function.file-exists.php

Particularly the notes about safe mode and caching.

Might help.

prometheos

hey thanks for the suggestion,
safe mode is off on the server im using... :S
Can anyone think of another way of going about this maybe?

prometheos

finally, headache gone!
i decided to not use the file_exists method.
my solution was this...
[php]
$filename = "./xml_files/".$user_id.".xml";
$file = fopen ($filename, "r");
if (!$file){
$xml = simplexml_load_file(filename);

$item = new SimpleXMLElement("<items></items>");
$hi = $item->addChild("item");
$hi->addChild("itemName",$item_n);
$hi->addChild("itemSource",$source);
$item->asXML($filename);

}else{

$xml = simplexml_load_file($filename);
$item = new SimpleXMLElement($xml->asXML());
$by = $item->addChild("item");
$by->addChild("itemName",$item_n);
$by->addChild("itemSource",$source);
$item->asXML($filename);
}
fclose($file);
[/php]

Thanks for the help guyz