How to access a public array inside a function in the same PHP object? Array returns NULL

Question

I'm writing a function in an object and need to access an array that gets constructed when the object is created. I can access normal variables inside the function using $this->var but I can't access an array in the same way using $this->array['key']. Why can't my function use arrays?

Here's the offending code:

class User
{
    public $_x;
    public $_y;
    public $_z;
    public $_array;

    public function __construct($username)
    {
        $_x = 'a';
        $_y = 'b';
        $_z = 'c';
        $_array = array( 'red' => $_x,  'blue' => $_y,  'green' => $_z,);
    }

    public function myFunction()
    {
        echo $this->_x . "<br>";
        echo $this->_y . "<br>";
        echo $this->_z . "<br>";
        echo $this->_array['red'] . "<br>";
        echo $this->_array['blue'] . "<br>";
        echo $this->_array['green'] . "<br>";
        var_dump($this->_array);
    }
}

$user = new User;
$user->myFunction();

Which displays:

a

b

c

NULL

Are you sure about that output?

revo
– revo

2016-08-31 14:16:17 +00:00
Commented Aug 31, 2016 at 14:16 — revo
– revo, Commented Aug 31, 2016 at 14:16

Marc B · Accepted Answer · 2016-08-31 14:10:02Z

1

You forgot $this:

public function __construct($username)
{
    $_x = 'a';  // LOCAL variable, exists only in the constructor
    $this->_x = 'a'; // class variable
    ^^^^^----you forgot this

answered Aug 31, 2016 at 14:10

Marc B

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Comments

Jeroen Noten · Accepted Answer · 2016-09-01 09:35:38Z

0

You have to use the $this keyword in the constructor too:

public function __construct($username)
{
    $this->_x = 'a';
    $this->_y = 'b';
    $this->_z = 'c';
    $this->_array = array( 'red' => $this->_x,  'blue' => $this->_y,  'green' => $this->_z,);
}

edited Sep 1, 2016 at 9:35

answered Aug 31, 2016 at 14:10

Jeroen Noten

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1 Comment

Progrock Over a year ago

Now $_x, $_y and $z are not defined for the array definition.

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