PHP global variable scope inside a class

Question

I have the following script

myclass.php

<?php

$myarray = array('firstval','secondval');

class littleclass {
  private $myvalue;

  public function __construct() {
    $myvalue = "INIT!";
  }

  public function setvalue() {
    $myvalue = $myarray[0];   //ERROR: $myarray does not exist inside the class
  }
}

?>

Is there a way to make $myarray available inside the littleclass, through simple declaration? I don't want to pass it as a parameter to the constructor if that was possible.

Additionally, I hope that you actually CAN make global variables visible to a php class in some manner, but this is my first time facing the problem so I really don't know.

Why? This is 180º away from common sense. And did you read the documentation at all? — Lightness Races in Orbit, Dec 13 '11 at 11:32
**Warning**: using global variables will quickly turn your code into an unmaintainable mess. Consider passing it as a parameter either to the constructor, or `setvalue()`, whichever is logical in your app. — kapa, Dec 13 '11 at 11:39
I did not 'read the documentation' since I did not even know what to look for. Thanks for the 'why global' suggestion. — roamcel, Dec 13 '11 at 11:39

score 18 · Accepted Answer · edited May 23 '17 at 12:34

18

include global $myarray at the start of setvalue() function.

public function setvalue() {
    global $myarray;
    $myvalue = $myarray[0];
}

UPDATE:
As noted in the comments, this is bad practice and should be avoided.
A better solution would be this: https://stackoverflow.com/a/17094513/3407923.

edited May 23 '17 at 12:34

Community

1
1

answered Dec 13 '11 at 11:32

Nick Shvelidze

1,564
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3

Please note that this is considered a bad practice (as well as `$GLOBALS`). – kapa Dec 13 '11 at 11:41
I'd say simply `setvalue($value)`, the array should not be relevant to the class. It just receives a value. But we do not know the app logic. – kapa Dec 13 '11 at 11:45
1

I'm marking this as the solution since it's technically the correct answer to my question. Anybody reading this in the future please note that such approach should be avoided if possible. – roamcel Dec 13 '11 at 11:45
6

Can we have an edit that points to a best practice alternative? – Evan Nov 26 '13 at 18:29
@Evan, "best practice" changes with time, culture, and use case. Facts don't. – Pacerier Mar 04 '15 at 07:57

score 3 · Answer 2 · answered Dec 13 '11 at 11:34

3

in a class you can use any global variable with $GLOBALS['varName'];

answered Dec 13 '11 at 11:34

macjohn

1,755
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18

score 1 · Answer 3 · edited Nov 19 '14 at 04:09

1

Construct a new singleton class used to store and access variables you want to use ?

edited Nov 19 '14 at 04:09

Pupil

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answered Dec 13 '11 at 11:57

jbrtrnd

3,815
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score 0 · Answer 4 · answered Dec 13 '11 at 11:31

0

 $GLOBALS['myarray'] =  array('firstval','secondval');

In the class you just might use $GLOBALS['myarray'].

answered Dec 13 '11 at 11:31

djot

2,952
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score 0 · Answer 5 · answered Dec 13 '11 at 12:10

Why dont you just use the getter and setter for this?

<?php

    $oLittleclass = new littleclass ;
    $oLittleclass->myarray =  array('firstval','secondval');

    echo "firstval: " . $oLittleclass->firstval . " secondval: " . $oLittleclass->secondval ;

    class littleclass 
    {
      private $myvalue ;
      private $aMyarray ;

      public function __construct() {
        $myvalue = "INIT!";
      }

      public function __set( $key, $value )
      {
        switch( $key )
        {
          case "myarray" :
            $this->aMyarray = $value ;
          break ;
        }
      }

       public function __get( $key )
       {
          switch( $key )
          {
            case "firstval" :
              return $this->aMyarray[0] ;
            break ;
            case "secondval" :
              return $this->aMyarray[1] ;
            break ;
          }    
       }   
    }

    ?>

a bit too complex for what can be otherwise accomplished with one line :) — roamcel, Dec 16 '11 at 15:56
@Amelia is this a solution for my question here http://stackoverflow.com/questions/33613200/php-define-variable-in-global-scope-and-use-it-in-a-class-function ? Thank you — thednp, Nov 09 '15 at 17:22

PHP global variable scope inside a class

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