从2个其他变量制作PHP变量

I'm starting a magazine which has 3 editions. UK, US, and European. Each will be published online at different times, therefore each has a different issue number.

So I want to create a way of selecting which issue goes with which edition, but I don't know how to join these 2 parts together. The code I'm using is:

<?php
$this_edition = "UK";
?>

<?php
$UK_issue = "1";
$US_issue = "3";
$EU_issue = "2";
?>

<?php
$this_issue = // The Issue Relating to This Edition
?>

What I want to do here is basically call the issue number ( 1/3/2 ) which relates to the $edition I'm udating, in this case, UK.

So essentially : $this_issue = $edition_issue

Does anyone know how I can do this?

What you're trying to do is possible...

$this_issue = ${$this_edition.'_issue'};

But it's way better to use the solution suggested by pr1nc3.

How about an array so you have keys and values to match?

For example $magazine = [1 => 'UK', 2 => 'US', 3 => 'EU'];

Array
(
    [1] => UK
    [2] => US
    [3] => EU
)

Your array keys (issues) match the country(edition)

You may use Associative Array as shown below.

<?php
$this_edition = "UK";
$edition['UK'] = 1;
$edition['US'] = 2;
$edition['EU'] = 3;
$this_issue = $edition[$this_edition];
?>

How about an array so you have keys and values to match?

$magazine = array(1 => 'UK', 2 => 'US', 3 => 'EU');
$issue=1;
echo $magazine[$issue];

output will be

UK

I think you have already got your answer, But just want to show you another way if you need to hold more details about your editions and issues in an array.

    <?php
    $this_edition = "UK";

    $editions = array("UK"=>array("name"=>"UK Edition","value"=>1), "US"=>array("name"=>"US Edition","value"=>2), "EU"=>array("name"=>"EU Edition","value"=>3));

    echo $this_issue = $editions[$this_edition]["name"];
    ?>

Output: UK Edition

If you keep your information inside mapped array, you will be able to receive them very easily at any point you need.