A question about php reference in array

a code segment:


$i = array('data'=>1000);

$arr = array('i'=>&$i);
$arr2 = $arr;

$i['data'] = 200;

print_r($arr);
print_r($arr2);

the result is:
Array
(
[i] => Array
(
[data] => 200
)

)
Array
(
[i] => Array
(
[data] => 200
)

)

This means the change of variable $i effects the $arr2 which is a copy
of $arr. Some one knows?

hi and hello wrote:
> $i = array('data'=>1000);
Here you have created that array


> $arr = array('i'=>&$i);
Here you said something like:
create an array with a field named 'i', and let
the field contain a link to $i variable

> $arr2 = $arr;
Here you have made a copy of the array,
like the above one, it has the 'i' field,
and the field contains the same link

It's like a link in your file system, when you copy a link,
it does not copy the original file.


> $i['data'] = 200;
Here you changed the value, it;s lieke you would change
what the file (in the file system) contains

When you print the arrays, PHP searched for the $i variable,
that is referenced by both tables and prints the reference target value.
That is what the reference is ment to do.

You can find more here:
php.net/manual/pl/language.references.php
Check out the examples in comments given by people.

best regards
Piotr N

On May 13, 1:41 am, Piotr <s...@poczta.onet.pl> wrote:
> hi and hello wrote:
> > $i = array('data'=>1000);
>
> Here you have created that array
>
> > $arr = array('i'=>&$i);
>
> Here you said something like:
> create an array with a field named 'i', and let
> the field contain a link to $i variable
>
> > $arr2 = $arr;
>
> Here you have made a copy of the array,
> like the above one, it has the 'i' field,
> and the field contains the same link
>
> It's like a link in your file system, when you copy a link,
> it does not copy the original file.
>
> > $i['data'] = 200;
>
> Here you changed the value, it;s lieke you would change
> what the file (in the file system) contains
>
> When you print the arrays, PHP searched for the $i variable,
> that is referenced by both tables and prints the reference target value.
> That is what the reference is ment to do.
>
> You can find more here:
> php.net/manual/pl/language.references.php
> Check out the examples in comments given by people.
>
> best regards
> Piotr N

Thanks for your excellent explaination.