我可以/如何...在 PHP 中的类之外调用受保护的函数

Question

I have a protected function that is defined within a certain class. I want to be able to call this protected function outside of the class within another function. Is this possible and if so how may I achieve it

class cExample{

   protected function funExample(){
   //functional code goes here

   return $someVar
   }//end of function

}//end of class


function outsideFunction(){

//Calls funExample();

}

Answer 1

Technically, it is possible to invoke private and protected methods using the reflection API. However, 99% of the time doing so is a really bad idea. If you can modify the class, then the correct solution is probably to just make the method public. After all, if you need to access it outside the class, that defeats the point of marking it protected.

Here's a quick reflection example, in case this is one of the very few situations where it's really necessary:

<?php
class foo { 
    protected function bar($param){
        echo $param;
    }
}

$r = new ReflectionMethod('foo', 'bar');
$r->setAccessible(true);
$r->invoke(new foo(), "Hello World");

Answer 2

That's the point of OOP - encapsulation:

Private

Only can be used inside the class. Not inherited by child classes.

Protected

Only can be used inside the class and child classes. Inherited by child classes.

Public

Can be used anywhere. Inherited by child classes.

If you still want to trigger that function outside, you can declare a public method that triggers your protected method:

protected function b(){

}

public function a(){
  $this->b() ;
  //etc
}

Answer 3

You can override this class with another where you make this public.

class cExample2 extends cExample {
  public function funExample(){
    return parent::funExample()
  }
}

(note this won't work with private members)

But the idea of private and protected members is to NOT BE called from outside.

Answer 4

If you want to share code between your classes you can use traits, but it depends how you want use your function/method.

Anyway

trait cTrait{
   public function myFunction() {
      $this->funExample();
   }
}

class cExample{
   use cTrait;

   protected function funExample() {
   //functional code goes here

   return $someVar
   }//end of function

}//end of class

$object = new cExample();
$object->myFunction();

This will work, but keep in mind that you don't know what your class is made of this way. If you change the trait then all of your classes which use it will be altered as well. It's also good practice to write an interface for every trait you use.

Answer 5

here i can give you one example like below

<?php
    class dog {
        public $Name;
        private function getName() {
            return $this->Name;
        }
    }

    class poodle extends dog {
        public function bark() {
            print "'Woof', says " . $this->getName();
        }
    }

    $poppy = new poodle;
    $poppy->Name = "Poppy";
    $poppy->bark();
?>

or one another way to use with latest php

In PHP you can do this using Reflections. To invoke protected or private methods use the setAccessible() method http://php.net/reflectionmethod.setaccessible (just set it to TRUE)

Answer 6

If the parent's method is protected, you can use an anonymous class:

class Foo {
    protected function do_foo() {
        return 'Foo!';
    }
}

$bar = new class extends Foo {
    public function do_foo() {
        parent::do_foo();
    }
}

$bar->do_foo(); // "Foo!"

https://www.php.net/manual/en/language.oop5.anonymous.php

Answer 7

Another option (PHP 7.4)

<?php
class cExample {
   protected function funExample(){
       return 'it works!';
   }
}

$example = new cExample();

$result = Closure::bind(
    fn ($class) => $class->funExample(), null, get_class($example)
)($example);

echo $result; // it works!

Answer 8

I am using Laravel. i was facing issue while access protected method outside of class .

   $bookingPriceDetails = new class extends BookingController {
        public function quotesPrice( $req , $selectedFranchise) {
           return parent::quotesPrice($req , $selectedFranchise);
        }
    };

     return $bookingPriceDetails->quotesPrice($request , selectedFranchisees());

here BookingController is Class name from which i want to get protected method. quotesPrice( $req , $selectedFranchise) is method that i want to access in different Class.