如何在php中使用类名作为case的switch case语句？

Is there a way to use the class names as cases in the folowing example? (pseudo code)

class Some_Class {

    static function get_image_size() {

        switch (get_class($image_size)) {

            case 'Class_1':
                        $image_size = 'related-post';
                        break;
                    }
            case 'Class_2':
                        $image_size = 'full';
                        break;
                    }                   

                        return $image_size;

                    }

}

I need this to call a specific variable form different php classes. Basically I need something like the following code but using switch statement:

class Some_class {

    static function get_image_size() {

        if Class_Name_1 {
            $image_size = 'related-post';
        }

        elseif Class_Name_2 {
            $image_size = 'full';
        }                   

        return $image_size;

    }

}

Thanks.