Question

This is something that’s been bugging me with PHP for a while now and I still can’t figure out how I would do it. Basically at the moment for my SQL class I’m dumping the results in an array and converting them to an object to give something like this:

$first_post = $Post->find(1);

(I’ve also been trying to get the syntax to look like: $Post::find(1); but that’s a different and purely aesthetic issue altogether)

and then you can use first_post like so:

$first_post->title;

This is done by just converting the contents of $post->find(1) to an object like so:

$first_post = (object) array("title" => "blah");

and I know that instantiates a new STDClass but I can’t figure out how to bind methods to that new instance of STDClass. It’s mainly so I can do stuff like:

$posts = $Post->all();
$last_post = $posts->last();
$specific  = $posts->find("name" => "hello");

Any ideas how I would get PHP to do something like this?

Answer 1

(I’ve also been trying to get the syntax to look like: $Post::find(1); but that’s a different and purely aesthetic issue altogether)

When using the scope resolution operator you are accessing static methods and/or constants. These are methods that work on the class rather than an instance of the class. For example:

// the find method retuns a new Post instance and 
// does not try to access $this
$post = Post::find(1);  

As for creating an object for the post from an array, it’s probably better to either create your own Post class and populate it accordingly or use one of the database functions that return the table data as an object rather than array such as mysqli_result::fetch_object or mysql_fetch_object.

If creating your own Post class, you can store the database information in an array and use the __call(), __get() and __get() Magic Methods to access that data. For example:

class Post() {
    protected $data;
    
    public function __construct($data) {
        $this->data = $data;
    }
    
    // access data with a getFoobar() style call
    public function __call($name, $args) {
        if (substr($name, 0, 3) == 'get') {
            $key = strtolower(substr($name, 3));
            if (array_key_exists($key, $this->data)) {
                return $this->data[$key];
            }
        }
        
        $class = get_class($this);
        throw new Exception("Call to undefined method $class::$name");
    }
    
    // access data like a class property
    public function __get($key) {
        if (array_key_exists($key, $this->data)) {
            return $this->data[$key];
        }
        
        throw new Exception("Attempt to access non-existant property $class::$name");
    }
    
    // set the data like a class property
    public function __set($name, $value) {
        $this->data[$name] = $value;
    }
}