Combine form values under one name using GET method - php

Question

I have a form using the GET method consisting of checkboxes.
This form is sending data to another page that is receiving the GET info and using it to pull info from a json api. I need to have it send the name once with all values combined into one string like this: example.com/color=RedGreenBlue
I am able to get all values combined and echoed onto the page but because they are in a foreach loop I am not able to pass them in the form. I tried below using the hidden field to pass them with no luck.
This is the method I've seen suggested but does not work for me:
<form action="" method="get">
Red<input type="checkbox" name="color[]" value="Red">
Green<input type="checkbox" name="color[]" value="Green">
Blue<input type="checkbox" name="color[]" value="blue">
<input type="submit" value="submit">
<?php
$name = $_GET['color'];
if (isset($_GET['color'])) {
foreach ($name as $color){
echo $color;
}
}
?>
<input type="hidden" name="MajorArea" value="<?php echo $color; ?>" />
</form>
Is there a way to assign one name to a group of checkboxes? Is there a way to pull the foreach loop data and use it outside a loop? Am I overlooking a way that is much easier than this?
Thanks for any advice!

Answer 1

I'll go out on a limb here and delete if it isn't what you're after. $_GET['color'] will be an array or it will be empty. You could also use isset:
<form action="" method="get">
Red<input type="checkbox" name="color[]" value="Red">
Green<input type="checkbox" name="color[]" value="Green">
Blue<input type="checkbox" name="color[]" value="blue">
<input type="submit" value="submit">
</form>
<?php
if (!empty($_GET['color'])) {
echo implode($_GET['color']);
}
?>