PHP question
 

Hi,
I've gone thru the PHP Tutorial on W3 and I've not seen reference to things such as

"$vbulletin->GPC['moderatorid']". Can anyone tell me what this operator (->) does ??

I'm not the best at explaining but these are sorta custom vBulletin commands.

-> sorta means this or next

So in the example you gave it's vbulletin this GCP

GCP is like a clean function so it's cleaning the contents of moderatorid

moderatorid is a varable which in this case is a number and represents the id number.

So the line you gave means "vBulletin this clean moderatorid"

Hope you follow me. As I said I'm not the best at explaining this sorta stuff.

I'm not sure what the technical term for it is but it's used for PHP's OOP (object-oriented programming). $vbulletin is a class and to access that classes members (variables of the class) or functions you can use the -> operator. So that just means that GPC['moderatorid'] is a member of the $vbulletin class. Quite a few programming languages use the same operator for this purpose.

EDIT: Posted this before seeing Happy's response. I'm not really sure that's a valid response. I don't know much about vBulletin itself/their functions etc but as far as I can tell the GPC there isn't a function it's just an array. I'm presuming this clean function that you mention sets this array up though. Plus I certainly weren't aware of -> being a custom vB command lol. It's part of PHP's programming language.

Sorry I know that is -> OOP isn't custom to vBulletin. I was refering to the whole $vbulletin->GPC command. As I said I'm not great at explaining things and was trying to explain it in simple English. If inenigma was using W3schools for tutorials I presumed he wanted it in an extremely simple English explanation. Sorry.

Cool. I can understand that. Is there a reference manual anywhere that would have all of the vBulletin classes and functions as I can see the "->" operator used all over the place in the code. I've got a good grounding in programming and want to learn PHP so I thought I'd buy vBulletin as investment in my education. If I can understand what the code is doing, then I can make changes to it...

API documentation is available through the member control panel at

http://members.vbulletin.com/api/index.html

-> is the equivalent of the dot operator in Java for accessing the methods and variables stored in an instance of a class.

If you had a database class that contained functions to do with a database (I'm not going to write it).

Your class is $db.
1 function is clean() to sanitise inputs for databases.
1 function is insert() to insert inputs into the database.
1 function is select() to select from the database.

Now, because these are contained in the $db class, we can access these functions as a child property of that class, by using the (->) operator.

$db->clean($_POST['somestuff']);
$db->insert($_POST['somestuff']);

I'm sorry if that didn't help, as Attilitus said it's used to access methods and variables that are stored inside your class.

Cool. Understand now. I'm new to PHP and had not seen reference to -> in any of the doco that I'd read and wanted to understand what it was doing.

Thanks Guys