继承静态值

Question

I'm strongly suspecting I'm designing my overall code wrong, but is it possible to inherit static values?

I have a base class, BaseModel, in which I have a __callStatic call. BaseModel extends into different model types, and in each, I have a public static $type; with a string value noting the type. When I call self::$type in the callStatic call in BaseModel, I get back null, which makes sense after the fact. However, I'm not sure then how I can get the type of the class making the call without copying the callStatic code into each class (not sure if I can put magic methods in traits?).

Right now, I'm not doing anything fancy:

public static function __callStatic($method, $params) {
    var_dump(self::$type);
}

in BaseClass. But I can't figure out how to approach this problem, if it's possible at all.

Answer 1

You are looking for Late Static Bindings, which could be used with the static keyword.

self (and also __CLASS__) is always evaluated at compile time, so it will always be executed without the knowledge of inheritance and the calling context.

static however tries to solve this limitation by evaluating the calling context at runtime.

class a {

    public static $foo = "A";

    public static function __callStatic($method, $params) {
        echo static::$foo . "
";
    }
}

class b extends a {
    public static $foo = "B";
}

a::test();
b::test();