Php - creating json object - php

Question

I am trying to create a json object from the data that I get from Ninja Forms that would look like this:
{
"title": "Contact Me",
"fields": [
{
"label": "Name",
"type": "textbox",
"required": "1"
},
{
"label": "Email",
"type": "email",
"required": "1"
}
]
}
I am trying to do so, like this:
$settings = ['label', 'type', 'required'];
$formTitle = Ninja_Forms()->form( 1 )->get()->get_setting('title');
$formFields = Ninja_Forms()->form(1)->get_fields();
$data = ['title' => $formTitle];
foreach ($formFields as $formField) {
$key = $formField->get_setting('key');
foreach ($settings as $setting) {
$data['fields'][$key][][$setting] = $formField->get_setting($setting);
}
}
return $data;
But, the result of that looks like this:
{
"title": "Contact Me",
"fields": {
"name": [
{ "label": "Name" },
{ "type": "textbox" },
{ "required": "1"}
],
"email": [
{ "label": "Email" },
{ "type": "email" },
{ "required": "1" }
],
How can I do this, so that the result looks like the one I have shown above?
I have also tried like this:
foreach ($settings as $setting) {
$data['fields'][] = $formField->get_setting($setting);
}
But, that gave me this kind of result:
{
"title": "Contact Me",
"fields": [
"Name",
"textbox",
"1",
"Email",
"email",
"1",
"Message",
"textarea",
"1",
"Submit",
"submit",
null
]
}

Answer 1

This gave me the wanted result:
foreach ($formFields as $formField) {
$key = $formField->get_setting('key');
foreach ($settings as $setting) {
$object[$setting] = $formField->get_setting($setting);
}
$data['fields'][] = $object;
}
return $data;

Answer 2

One way to look at this is to count the dimensions of the data. In your desired format, the deepest item is:
{ "fields": [ { "label": "Name"
So you have object -> array -> object.
If we indent each array in your code, we have:
$data // outermost array
['fields']
[$key]
[] // innermost array
[$setting] = $value; // key in innermost array
Or if we were to declare it with just one value:
$data = array(
'field' => array(
$key => array(
0 => array(
$setting => $value
)
)
)
);
So you have 4 levels of array, instead of 3.
Comparing to the JSON, taking an array with numeric keys as "array" and one with non-numeric keys as "object", the pattern is object -> object -> array -> object.
So it's the [$key] we need to eliminate, because it's creating an extra object dimension.
But we don't want to increment the key at [] for each item either, so we need to either make our value in advance...
foreach ($settings as $setting) {
$object[$setting] = $formField->get_setting($setting);
}
$data['fields'][] = $object;
...or choose our key in advance:
$i++;
foreach ($settings as $setting) {
$data['fields'][$i] = $formField->get_setting($setting);
}