randomizer randomizer - 5 months ago 14
PHP Question

PHP class constructor in interface or class

I'm having some issues thinking out a good structure to build my classes and objects.
In the code below I make use of an interface to define my class methods, but I also want to pass a database connection to my constructor so the class had this connection to work with.
Is it correct as I coded it below that the constructor is placed within my class and the methods in my interface?

interface IDataItem
{
public function saveItem(Item $theItem);
}

class DataItem implements IDataItem{
public function __construct(Database $database)
{
$this->database = $database;
}

public function saveItem(Item $item)
{
//save the item
}
}


$db = new Database(); //from a database class
$dataItem = new DataItem($db);
$dataItem->saveItem($anItem);

Answer

I don't personally think you should put the constructor in the interface because you'd never create a new object without being aware of which implementation you're using.

There is a mistake in your code, the method in an interface cannot have an implementation, it needs to be just a declaration, like this

interface IDataItem
{
    public function saveItem($theItem);
}
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