Zend Preparation | PHP Quiz (Learning Mode)

OOP Learning Mode

Qusetions Index 136/246

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You run the following PHP script:

<?php
   class number {
       public $a= 10;
      public $b=20;
      private $c=30;
}
    $numbers = new number();

     foreach($numbers as $var => $value) {
       echo "$value ";
   }
?>

What will be the output?

10 20

The script will throw an error.

10 20 0

10 20 30

Explanation: Answer option A is correct.

In the given script, $c variable is not in the output because it is marked Private and we are trying to access it from the global scope. Hence, the $c variable cannot be accessed in the global scope and the output will be as follows:

10 20

However, you can see private variables too when the object itself looped through its variables. For example, in the given script private as well as public both the variables are assessable:

 <?php
 class number {
 public $a= 10;
 public $b=20;
 private $c=30;

 public function output() {
 foreach($this as $var => $value) {
 echo "$var is $value ";
 }
 }
 }

 $numbers = new number();
 $numbers->output();
?>

Output: 10 20 30