How do I add more information to an object?

Question

Let us suppose I have the following object:

{
    foo: "bar"
}

How do I, using javascript, make it:

{
    foo: "bar",
    bar: "foo"
}

Answer 1

You simply need to assign it a new property using dot notation:

const data = {
  foo: "bar"
};

data.bar = 'foo';

console.log(data);

If your property names are variables, use bracket notation instead:

const data = {
  foo: "bar"
};

const newProp = 'bar';
data[newProp] = 'foo';

console.log(data);

See the doc on property accessors here.