php - Why pass variables to a class instead of method -

i wondering benefit of passing parameters class rather method.

in terms of code, what's benefit of doing this:

$books = new books($book_id, $book_name); 

instead of

$books = new books; $books->setbook($book_id, $book_name); 

thanks!

"passing class" not thing. new foo($bar, $baz) instantiating new object , passing parameters constructor method:

class foo {      public function __construct($bar, $baz) {         ...     }  } 

there's no difference such between passing parameters regular method , constructor. difference constructor called when object instantiated, , other methods called anytime later.

you should pass parameters constructor object requires @ construction time. typically means pass parameters required object work @ all. constructor can throw exception if doesn't parameters, means object fail instantiate @ all. guarantees object in known, consistent state. compare:

$api = new fooapi($id, $password); $api->dosomething();  $api = new fooapi; // $api->setid($id); // $api->setpassword($password); $api->dosomething();  // error! no id , password given