Member Avatar for UI

Good Weekend Folks!

I have a question.
I do not understand how php knows how to define this variable $value in the following example since it has not been declared. How does it know what that variable represents since no reference or pointer has been assigned to it ? Strange!

https://www.tutorialspoint.com/php/php_arrays.htm

<html> <body> <?php
         /* First method to create array. */
         $numbers = array( 1, 2, 3, 4, 5);

         foreach( $numbers as $value ) {
            echo "Value is $value <br />";
         }

         /* Second method to create array. */
         $numbers[0] = "one";
         $numbers[1] = "two";
         $numbers[2] = "three";
         $numbers[3] = "four";
         $numbers[4] = "five";

         foreach( $numbers as $value ) {
            echo "Value is $value <br />";
         }
      ?> </body> </html>

I thought "array_values()" was supposed to be there in the above example but "$value" is there instead.
What is the difference between the 2 ?

https://www.tutorialspoint.com/php/php_array_functions.htm
The following seems to be in pdo, which I haven't started learning just yet:
https://www.tutorialspoint.com/php/php_function_array.htm

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Member Avatar for rubberman

$value is a dynamic variable that only lives within the scope of the loop it is used in. You have declared it with the loop declaraction.

Member Avatar for jkon

As rubberman wrote you declared the $value inside the foreach for this array iteration.

@see http://php.net/manual/en/control-structures.foreach.php

There are more than that about arrays iteration in PHP (and differences in versions) but I don't want to mess you with these.

Just a quick comment , $value doesn't "live" only within the scope of the loop it is used in.
e.g. 

$arr = ["a","b","c"];
foreach($arr as $value)
{
    //code
}
echo $value;
Member Avatar for UI

Elsewhere, I understood from another programmer's hints that, the $numbers value would increment on each loop to $value.
The $numbers value would remain the same on each loop but not the $value's value.
I get it now.

This thread can be closed now so how do I close it ?

Thanks!

Edited by UI
Member Avatar for diafol

Press the big solved button. Only you can do this. Threads can only be closed by moderators. This is almost never done unless a thread spirals out of control for some reason.

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