Add a value to an JSON array object

Question

I have an array that looks like this

[{
 "Inventory": {
 "dashboard_id": "Inventory",
 "filter_by": "Location",
 "yAxis": "Quantity",
 "title": "",
 "chart_type": "-------Select-------",
 "mainchart": "Yes"
 },
 "Quality": {
 "dashboard_id": "Quality",
 "filter_by": "Location",
 "yAxis": "SampleNo",
 "title": "",
 "chart_type": "-------Select-------",
 "mainchart": "Yes"
 }
}]

I need to add more values into each object. How do I ADD to an existing array so it might look something like this

{
 "Inventory": [{
 "dashboard_id": "Inventory",
 "filter_by": "Location",
 "yAxis": "Quantity",
 "title": "",
 "chart_type": "-------Select-------",
 "mainchart": "Yes"
 }, {
 "dashboard_id": "Inventory",
 "filter_by": "Location",
 "yAxis": "Quantity",
 "title": "",
 "chart_type": "-------Select-------",
 "mainchart": "Yes"
 }],
 "Quality": {
 "dashboard_id": "Quality",
 "filter_by": "Location",
 "yAxis": "SampleNo",
 "title": "",
 "chart_type": "-------Select-------",
 "mainchart": "Yes"
 }
}

I add into the array using nestedData[dashId] = data;

Where dashId consist of Quality, 'Inventory', etc.

data is

{
 "dashboard_id": "Inventory",
 "filter_by": "Location",
 "yAxis": "Quantity",
 "title": "",
 "chart_type": "-------Select-------",
 "mainchart": "Yes"
}

Answer 1

Build a new Object using the literal syntax, which contains the desired arrays and assigns the objects from the source array to the respective property in the object.

var arr = [{
 "Inventory": {
 "dashboard_id": "Inventory",
 "filter_by": "Location",
 "yAxis": "Quantity",
 "title": "",
 "chart_type": "-------Select-------",
 "mainchart": "Yes"
 },
 "Quality": {
 "dashboard_id": "Quality",
 "filter_by": "Location",
 "yAxis": "SampleNo",
 "title": "",
 "chart_type": "-------Select-------",
 "mainchart": "Yes"
 }
}];
var obj = {Inventory:[arr[0].Inventory], Quality:[arr[0].Quality]};
obj.Inventory.push({
 "dashboard_id": "Inventory",
 "filter_by": "Location",
 "yAxis": "Quantity",
 "title": "",
 "chart_type": "-------Select-------",
 "mainchart": "Yes"
});
console.log(obj);

Working Example: http://jsfiddle.net/vJjSX/