How do I access deeper levels of a json tree using curl? - php

Question

I'm trying to learn how to use CURL and Json to access data sent from the Facebook graph api.
I'm using the following function which pulls the post data:
function loadFB($fbID){
$url="https://graph.facebook.com/".$fbID."/feed?limit=1&access_token=xxxx";
$c = curl_init($url);
curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
$page = json_decode(curl_exec($c));
curl_close($c);
$post=reset($page->data);
if($post->message == '') {
$post_msg = '' . $post->name . '';
} else {
$post_msg = $post->message;
}
return $post_msg;
}
Example JSOn data looks like this:
{
"data": [
{
"id": "xxxx",
"from": {
"name": "xxx",
"category": "xxx",
"id": "xxx"
},
"picture": "xxxxxxxxx",
"link": "xxxxxxx",
"name": "Event name goes here",
"properties": [
{
"text": "Friday, July 15, 2011 at 4:00pm"
},
{
"text": "Venue Name"
}
],
"icon": "http://static.ak.fbcdn.net/rsrc.php/v1/yW/r/r28KD-9uEMh.gif",
"type": "link",
"object_id": "xxx",
"created_time": "2011-06-23T06:46:17+0000",
"updated_time": "2011-06-23T06:46:17+0000",
"likes": {
"data": [
{
"name": "xxxx",
"category": "xxx",
"id": "xxxx"
}
],
"count": 1
}
}
],
"paging": {
"previous": "xxxxx",
"next": "xxx"
}
}
As it stands, I can retrieve the message of a page update, or if its an event I can retrieve the event name and the link for the event.
But what if I want to retrieve say the event date or the venue name? Its under another tier of 'properties'.
With my code so far, I can access the first level of things with $post->message, but when I try $post->properties->text this doesn't work - so I don't understand how this works. On top of that, in the 'properties', there's 2 'text' which is adding to my confusion of how to access these things.
Any pointers?

Answer 1

$post->properties is an array so :
$post->properties[0]->text;

Answer 2

Properties in the data above is an INDEXED ARRAY so you want $post->properties[x].text where x is 0 for the first item and 1 for the second item, etc...