parse next value from xml feed on page refresh - php

Question

I have an xml feed that I can access using simplexml_load_file and using for each access all of the records in it. I am also able to access an individual node using the following:
$xml->property[0]->propertyID;
What I want to be ble to do is to indvidually display each record in turn, ie move from [0] to [1] and so on in turn on page refresh but don't know how to go about that.
I'm just a hobbyist so please forgive me if this is a bit of newb question

Answer 1

You need to introduce some state somewhere, so that you can remember where you've got to.
You can either have the browser count up each time the page is refreshed using a cookie, or you can remember this on the server side by storing the current node number somewhere - in a database, in a file, or in the URL.
Probably the simplest thing to do is to tack the next node number onto the end of the URL, so when that page is reloaded, you'll see that parameter on the server side and can load that node. Something like this:
$node = 0;
if (empty($_GET['nextnode']))
{
header('Location: example.php?nextnode=' . node + 1);
} else {
$node = $_GET['nextnode'];
}
...
$xml->property[$node]->propertyID;
When the page is refreshed it will make a request to your PHP script, as normal, but it'll have something like this on the end of the requested URL:
?nextnode=23
PHP will store these URL parameters in the $_GET array, which you can then query in your script. Look up the documentation on header for more information.
Another, similar, technique is to store the value in a hidden form field when you create the page in PHP:
echo '<form>
<input type="hidden" value="'.$node + 1.'" />
<input type="submit" value="Next Node" />
</form>';
This will be create a 'Next Node' button on the page, and will get sent back to you as a form submission when someone clicks it. You can then lookup the next node and redisplay the page. See here for more info on dealing with forms in PHP.