PHP Create Multidimension Array for JSON output - php

Question

I feel terrible even asking because I have been TRYING to understand and comprehend other peoples examples this is what i'm TRYING to accomplish
{
"field": [
{
"appid": 0,
"page": 0,
"fieldname": "Sweet",
"value": "Tammy Howell"
},
{
"appid": 1,
"page": 1,
"fieldname": "Cecilia",
"value": "Shana Jordan"
},
{
"appid": 2,
"page": 2,
"fieldname": "Merritt",
"value": "Copeland Pena"
}
]
}
I need to be able to make the above JSON output happen when doing an SQL SELECT statement
Here is my currentCode
$x = 0;
$userFieldsResult = mysqli_query($database_id, "SELECT * FROM theDB.DynamicFields ORDER BY Page, Priority") or die (mysqli_error($database_id));
if (mysqli_num_rows($userFieldsResult)<=0)
{
echo "nothing found";
exit;
} else
{
while($row = mysqli_fetch_array($userFieldsResult))
{
$userFields[$x]['appid'] = $row['appid'];
$userFields[$x]['page'] = $row['page'];
$userFields[$x]['fieldname'] = $row['fieldname'];
$userFields[$x]['value'] = $row['value'];
$x++;
}
echo json_encode($userFields);
exit;
}
echo json_encode($userFields);
This is normally how i just been outputting json so they each are just part of 1 array looping, but I am trying to understand how to create more "in-depth" JSON arrays so they have a specific identifier before they list out the information.
[
{
"appid": 0,
"page": 0,
"fieldname": "Sweet",
"value": "Tammy Howell"
},
{
"appid": 1,
"page": 1,
"fieldname": "Cecilia",
"value": "Shana Jordan"
},
{
"appid": 2,
"page": 2,
"fieldname": "Merritt",
"value": "Copeland Pena"
}
]
In my example I just want to be able to have "field" be the "upper" part of the array that holds all the information as i showed in the example above.

Answer 1

You need to add field as parent array to your array.
Change from
echo json_encode($userFields);
Into
$json = array('fields' => $userFields);
echo json_encode($json);

Answer 2

In this particular configuration, you are being returned an object with properties, of which, the property's value may be an array.
So what you should actually be doing is creating a stdClass object in PHP and assigning it a property of "field" which is an empty array. Then you can push into this array stack.
$obj = new stdClass();
$obj->fields = array();
while(....){
$obj->fields[$x]['appid'] =
$obj->fields[$x]['appid'] = $row['appid'];
$obj->fields[$x]['page'] = $row['page'];
$obj->fields[$x]['fieldname'] = $row['fieldname'];
$obj->fields[$x]['value'] = $row['value'];
}
Now you can json encode the object and return it.
echo json_encode($obj);