php - Alternative to 'if' statement inside array - php

Question

I've been reading around and cannot find a solution that works for the requirement I have. I need to dynamically add values to the 'add' part of this array depending on conditions. I know that you cannot put any if statements inside the array itself.
The correct syntax (from the documentation) is:
$subResult = $gateway->subscription()->create([
'paymentMethodToken' => 'the_token',
'planId' => 'thePlanId',
'addOns' => [
'add' => [
[
'inheritedFromId' => 'addon1',
'amount' => '10'
],
[
'inheritedFromId' => 'addon2',
'amount' => '10'
]
]
]
]);
From what I had read on a similar question on SO, I tried the following (where $addon1 and $addon2 would be the conditions set earlier in the code)
$addon1 = true;
$addon2 = true;
$subResult = $gateway->subscription()->create([
'paymentMethodToken' => 'the_token',
'planId' => 'thePlanId',
'addOns' => [
'add' => [
($addon1 ? array(
[
'inheritedFromId' => 'productAddon1Id',
'amount' => '10'
]) : false),
($addon2 ? array(
[
'inheritedFromId' => 'productAddon2Id',
'amount' => '10'
]) : false)
]
]
]);
But I get back a Warning: XMLWriter::startElement(): Invalid Element Name so I suspect that it does not like the structure and the code fails with a fatal error (interestingly, if I only set the first $addon to true it still comes up with the warning, but does actually work. With two it fails).
Is there another way to do this or did I get the syntax wrong?
I cannot hardcode all the possibilities due to the amount of possible product combinations.
Would appreciate and help. Thank you.

Answer 1

Don't try to do everything at once.
$add = [];
if( $addon1)
$add[] = ['inheritedFromId'=>.......];
if( $addon2)
.....
$subResult = $gateway->subscription()->create([
'paymentMethodToken' => 'the_token',
'planId' => 'thePlanId',
'addOns' => [
'add' => $add
]
]);

Answer 2

you can put if statements in array declarations, it's called ternary operations:
$myArray['key'] = ($foo == 'bar' ? 1 : 2);
this is the basis of how to use.

Answer 3

You're using the array() syntax together with the short array syntax ([]). See the manual. This means that e.g. your first element in add would be an array within an array. Perhaps that's why the XML error is occurring? Better would be:
'add' => [
($addon1 ?
[
'inheritedFromId' => 'productAddon1Id',
'amount' => '10'
] : null),
($addon2 ?
[
'inheritedFromId' => 'productAddon2Id',
'amount' => '10'
] : null)
]
]

Answer 4

Your syntax is fine. you are creating array with this structure
array (size=3)
'paymentMethodToken' => string 'the_token'
(length=9)
'planId' => string 'thePlanId'
(length=9)
'addOns' =>
array (size=1)
'add' =>
array (size=2)
0 =>
array (size=1)
...
1 =>
array (size=1)
...
My quess is that $gateway->subscription()->create() is does not like this structure of your array. Maybe the 'false' as value or the numeric keys. Check what does it expect and try again with new structure of the array.