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PHP Extending Object-Oriented PHP Inheritance Extend a Class

Posted by Julie Dowler
Julie Dowler
7,851 Points

Don't know what's wrong here...

I'm doing the "Extending Object-Oriented PHP" Challenge Task 2 of 3. Here's the instructions: Challenge Task 2 of 3

Step 1: Add an additional array property to the Developer class named $skills that CANNOT be accessed from outside that class, but CAN be accessed by a child.

Step 2: Create a public facing GETTER named "getSkills" that will return the $skills property as an array.

Step 3: Create a public facing SETTER named "setSkills" that will accept an array and set the $skill property to that array value.

So, I entered this code and I get this error: Bummer! The "skills" property should be set to the parameter passed to the method.

I think I'm setting $skills to the parameter passed to the method. Does anyone know what's wrong?

User.php 
<?php
//do not modify this file
class User {
    protected $name;
    protected $title;

    public function __construct($name = null, $title = null) {
        $this->name = $name;
        $this->title = $title;
    }

    public function __toString() {
        return $this->getSalutation();
    }

    public function getSalutation() {
        return $this->title . " " . $this->name;
    }

    public function getName() {
        return $this->name;
    }

    public function setName($name) {
        $this->name = $name;
    }

    public function getTitle() {
        return $this->title;
    }

    public function setTitle($title) {
        $this->title = $title;
    }
}
Developer.php 
<?php
class Developer extends User
{
  protected $skills = array();

  public function getSkills()
  {
    return $this->$skills;
  }

  public function setSkills($anArray)
  {
    foreach($anArray as $skill)
    {
    $this->$skills[] = $skill;
    }
  }
}
//add new child class here

10 Answers

Sean T. Unwin
Sean T. Unwin
28,690 Points

Remove the dollar sign($) from the variable name(s) after $this->... in each function (get and set).

e.g. $this->skills

Heber Pavon
Heber Pavon
4,456 Points
Heber Pavon
Heber Pavon
4,456 Points

Hope this helps guys!

class Developer extends User
{
  protected $skills = array();

  public function getSkills()
  {
    return $this->skills;
  }

  public function setSkills($string)
  {

      $this->skills = $string;
  }
}
Xheni Myrtaj
PLUS
Xheni Myrtaj
Courses Plus Student 2,636 Points
Xheni Myrtaj
Xheni Myrtaj
Courses Plus Student 2,636 Points

<?php class Developer extends User { protected $skills = array();

public function getSkills() { return $this->skills; }

public function setSkills($array) { $this->skills = $array;

} } //add new child class here

Sean T. Unwin
Sean T. Unwin
28,690 Points
Sean T. Unwin
Sean T. Unwin
28,690 Points

In the body of setSkills() :

$this->$skills = $anArray;

If you wanted to be robust you could check if $anArray is, in fact, an array via:

 if (is_array($anArray) {
    $this->$skills = $anArray;
}
codingchewie
codingchewie
8,764 Points

Shouldn't it be $this->skills = $anArray; without the dollar sign for skills?

Julie Dowler
Julie Dowler
7,851 Points
Julie Dowler
Julie Dowler
7,851 Points

I already tried that. I tried it again just to be sure. It didn't work the second time either. Here's what I entered:

<?php
class Developer extends User
{
protected $skills = array();

  public function getSkills()
  {
    return $this->$skills;
  }

  public function setSkills($anArray)
  {
    $this->$skills = $anArray;
  }
}
//
Sean T. Unwin
Sean T. Unwin
28,690 Points
Sean T. Unwin
Sean T. Unwin
28,690 Points

For some reason the Challenge doesn't like the use of $this when setting the class variable from the setSkills function.

Using self::$skills = $anArray; or static::$skills = $anArray; works, however.

In my OP when I tested the challenge, I think I used static::$skills out of habit so my apologies there.

Julie Dowler
Julie Dowler
7,851 Points
Julie Dowler
Julie Dowler
7,851 Points

That didn't work. The property $skills was not declared as static, so referring to it as static shouldn't work. The error message says "Use $this to refer to internal properties". I get that error message regardless of whether I use $this or static:: or self::

Chris Craigman
Chris Craigman
13,659 Points
Chris Craigman
Chris Craigman
13,659 Points

Here's what worked for me.

<?php

//add new child class here class Developer extends User { protected $skills = array();

public function getSkills() { return $this->skills; }

public function setSkills($skills) { $this->skills = $skills; } }

Andras Guseo
Andras Guseo
621 Points
Andras Guseo
Andras Guseo
621 Points

Here's my full solution:

<?php

//add new child class here
class Developer extends User {
  protected $skills = array();

    public function getSkills() {
        return $this->skills;
    }

    public function setSkills( $skills ) {
        $this->skills = $skills;
    }

  function displayUserSkills() {
    $name = $this->getName();
    $skills = $this->getSkills();

    $string =  $name . ' has the following skills: ' . implode( ', ', $skills );

    return $string;

  }
}

$one = new Developer();
$one->setName('Alana');
$one->setSkills( ['PHP', 'MySQL', 'HTML' ] );

//var_dump($one);
echo $one->displayUserSkills();

The trick is that you cannot set the skills one by one, like:

$one->setSkills( 'PHP' );
$one->setSkills( 'MySQL' );
$one->setSkills( 'HTML' );

It needs to be set as an array, like this:

$one->setSkills( ['PHP', 'MySQL', 'HTML' ] );

or the old-fashioned way:

$one->setSkills( array( 'PHP', 'MySQL', 'HTML' ) );

Hope this will be helpful.

Julie Dowler
Julie Dowler
7,851 Points
Julie Dowler
Julie Dowler
7,851 Points

That worked. Thank you!