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phpoopvariable-variables

PHP get_called_class() as variable for referencing static property


I'm trying every variation of the following to refer to a static property:

get_called_class()::$$prop

I've tried this:

${get_called_class()}::$$prop

I've tried many things, but can't seem to get it.

I know I can just do this:

$className = get_called_class();
$className::$$prop

BUT, that means an extra line of code. Surely there must be a way for the language to make this work on the same line. Anyone have a solution?

(By the way, the static property is protected, so it fails with ReflectionClass::getStaticPropertyValue.)


Solution

  • Without understanding any additional context here, you don't need to actually invoke get_called_class to poke at LSB-resolved static properties. Instead, use the static keyword to automagically resolve the currently called static class name.

    class A {
    
        static $foo = 'from a';
    
        public static function test($property) {
            echo static::$$property, "\n";
        }
    
    }
    
    class B extends A { static $foo = 'from b'; }
    class C extends A { static $foo = 'from c'; }
    

    Example from the PHP interactive prompt:

    php > include '/tmp/get_called_class.php';
    php > A::test('foo');
    from a
    php > B::test('foo');
    from b
    php > C::test('foo');
    from c
    php >