php constant in oops being changed by the class object

Question

Today i was reading constant in oops and got confused by a piece of code na dcould not make out the reason for it the code is given below:

<?php
class myClass1
{
    const ID=1;
    private $name;

    public function get_name()
    {
        return $this->name ."<br>";
    }

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

$myClass1_object = new myClass1();

$myClass1_object->ID=2;

print("<br>".$myClass1_object->ID);
?>

I want to know the reason that how can a constant variable i.e const ID=1 is being changed by the the class object i.e $myClass1_object->ID=2; and in print statement i get the updated value i.e 2.

You print another field (created by accessing it via magic method), not constant. Access constant using this syntax: `myClass1::ID` — Phantom, Jun 27 '14 at 11:30
One thing yet. What is aim to use CONST in class? Senseless. You have static properties — turson, Jun 27 '14 at 11:37
@turson Some people are anti-static because they are evil. You can use Definitions though — Artemkller545, Jun 27 '14 at 11:38
Take a look at http://stackoverflow.com/questions/1685922/php5-const-vs-static — onuri, Jun 27 '14 at 11:39
ok then is there any method by which i can prevent the value of ID by being changed — Anurag Singh, Jun 27 '14 at 12:04

Phantom · Accepted Answer · 2014-06-27T11:50:16.623

2

If you try to access undefined object property PHP creates it for you:

$obj = new stdClass();

$obj->hello = 'world';

So you created just another field ID when you try to access your constant such way. Try to print constant value at the end of your script:

echo myClass1::ID;

and it should still be 1

edited Jun 27 '14 at 11:50

answered Jun 27 '14 at 11:44

Phantom

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php constant in oops being changed by the class object

1 Answers1