JavaScript: Constructing a Simple JSON Object Dynamically

1. Create an initial JSON object with a single element and an array:

   // {$id} is a PHP variable but it can be anything else
   jsonObj = {"id" : "{$id}", "myArray": []};

2. Construct the JSON object
   item = {}
   item ["id"] = "some Id";
   item ["value"] = "Some Value";
   jsonObj.myArray.push(item);

3. Output JavaScript:
   Object {id: "564f48ba-e9d5-463a-2325-58f91c653aa8", myArray: Array(1)}
   
   where myArray is broken down as follows:
   myArray: Array(3)
      0: Object
         id: "Some Id",
         value: "Some Value"

4. Output PHP:
   Array
   ( 
     [id] => 564f48ba-e9d5-463a-2325-58f91c653aa8
     [myArray] => Array
     (
          [0] => Array
          (
               [id] => Some Id
               [value] => Some Value
          )
     )
   )