[zodehala]

i can not understand what a strcuture ?

PHP Code:

$vbulletin->db->query_first(""); 

how can i make like above ? would you give me a simple tutorial like it ?

[UnrealEd]

this structure is used to call methods and fields from a certain class.
in this case there's an object (in the variable $vbulletin) or a certain class. That class has a field named 'db', which is an object itself. The db object has method query_first. So now you're calling the method query_first of the db object that is a field of the $vbulletin object

here's a small example:

PHP Code:

class Foo{
  public $bar;
  
  public function __construct(){
    $this->bar = new Bar;
  }
}

class Bar{
  public function bark(){
    echo "woof! woof!";
  }
}

$my_object = new Foo; // instantiates a new object of the Foo class
$my_object->bar->bark(); // will output "woof! woof!" 

Hope this makes it a little clearer, if not, let me know

UnrealEd