What does this mean in oop? $this->db->query

[Clandestinex337]

I understand what $this->db means, its accessing the variable db, but when you add the extra -> to the end what does that do? Its very hard to research information on this since Google doesn't help to much when using -> in the search.

 

Thanks

[wildteen88]

Its just calling the query function within the database object ($this->db).

 

I think this is known as object chaining.

 

 

[Clandestinex337]

Thanks, that makes sense. Instead of making another post, I will just put it in here.

 

The other part of the code I am trying to learn has public function __construct(MySql $db, $id = 0)

 

I am confused on the MySql $db. Does it give the class MySql = $db?

 

Thanks again!

[wildteen88]

That is called type hinting. Which mean it is enforcing that the $db argument must be an instance of the MySQL object when the parent class is initiated.

[Clandestinex337]

Thanks!