我可以在Child类中更改任何父函数的访问修饰符吗？

Question

Can I change the access modifiers of any parent function in Child class?

Answer 1

Child classes may only "loosen" the visibility, e.g.

class ParentClass
{
    protected function foo() {} 
}

can be

class ChildClass extends ParentClass 
{  
    public function foo() {} 
}

but not

class ChildClass extends ParentClass 
{  
    private function foo() {} 
}

---

Apart from that, you can use the Reflection API to change Visibility at runtime:

• ReflectionMethod::setAccessible — Set method accessibility

though you should ask yourself why you would want to do that. Usually parent classes that hide methods or properties from their children do so for a reason.