Objects does not support push property, but you can save it as well using the index as key,

var tempData = {};
for ( var index in data ) {
  if ( data[index].Status == "Valid" ) { 
    tempData[index] = data; 
  } 
 }
data = tempData;

I think this is easier if remove the object if its status is invalid, by doing.

for(var index in data){
  if(data[index].Status == "Invalid"){ 
    delete data[index]; 
  } 
}

And finally you don't need to create a var temp –

so it's easy)))

Watch this...

    var stuff = {};
    $('input[type=checkbox]').each(function(i, e) {
        stuff[i] = e.checked;
    });

And you will have:

Object {0: true, 1: false, 2: false, 3: false}

Or:

$('input[type=checkbox]').each(function(i, e) {
    stuff['row'+i] = e.checked;
});

You will have:

Object {row0: true, row1: false, row2: false, row3: false}

Or:

$('input[type=checkbox]').each(function(i, e) {
    stuff[e.className+i] = e.checked;
});

You will have:

Object {checkbox0: true, checkbox1: false, checkbox2: false, checkbox3: false}

You could add some properties of an object simply like this :

obj = {a : "1", b : "2"};

myObj = {c: "3", d : "4"};
myObj.a = obj.a;
myObj.b = obj.b;

Update:

In that case just do this :

for(var prop in obj) myObj[prop] = obj[prop];

And to filter out the unwanted properties inside the loop body you could also do this :

for (var prop in obj) {
    if (obj.hasOwnProperty(prop)) {
        myObj[prop] = obj[prop];
    }
}

If your JSON is without key you can do it like this:

library[library.length] = {"foregrounds" : foregrounds,"backgrounds" : backgrounds};

So, try this:

var library = {[{
    "title"       : "Gold Rush",
        "foregrounds" : ["Slide 1","Slide 2","Slide 3"],
        "backgrounds" : ["1.jpg","","2.jpg"]
    }, {
    "title"       : California",
        "foregrounds" : ["Slide 1","Slide 2","Slide 3"],
        "backgrounds" : ["3.jpg","4.jpg","5.jpg"]
    }]
}

Then:

library[library.length] = {"title" : "Gold Rush", "foregrounds" : ["Howdy","Slide 2"], "backgrounds" : ["1.jpg",""]};

I think you are mixing up objects and arrays. Objects have named keys, arrays have numeric keys. You can easily append to an array using .push():

var arr = [];
arr.push("something");

However, for a configuration object as your variable name suggests this is not really useful. You should rather use meaningful names for your options, e.g.:

var config = {
    something: 'blah',
    foo: 'bar'
};

You can also store an array in your object:

config.manyStuff = [];
for(...) {
    manyStuff.push(...);
}

You can also avoid using a superfluous var by creating an inline object:

newIssueList.push({
    Id: i,
    Number: 233 + i,
    Name: "Test" + i.toString()
});

The line of code below defines element as a plain object.

let element = {}

This type of JavaScript object with {} around it has no push() method. To add new items to an object like this, use this syntax:

element[yourKey] = yourValue

To put it all together, see the example below:

let element = {} // make an empty object

/* --- Add Things To The Object --- */

element['active'] = true // 'active' is the key, and 'true' is the value
console.log(element) // Expected result -> {active: true}


element['state'] = 'slow' // 'state' is the key and 'slow' is the value
console.log(element) // Expected result -> {active: true, state: 'slow'}

On the other hand, if you defined the object as an array (i.e. using [] instead of {}), then you can add new elements using the push() method.