How to conditionally add attribute to an object?

Question

I would like to conditionally add an attribute to an object. Currently I have this:

    const obj = {
    name: car.name,
    battery: car.battery && car.battery, 
    fuel: car.fuel && car.fuel
}

The problem is that if car.battery is not present I have battery: undefined. I would rather prefer not having that attribute in the object if it is not present. How can I achieve that?

Though, really… what are you doing here? You're just making a copy of the `car` object in a really verbose way. — deceze, Dec 06 '17 at 09:18
If you want to solve this inline, you can use `battery: car.battery || 'something else if falsy'`. Beware though, that if `car.battery` is `0`, you will get `'something else if falsy'` — JanS, Dec 06 '17 at 09:19

score 2 · Answer 1 · answered Dec 06 '17 at 09:19

The problem is that if car.battery is not present I have battery: undefined. I would rather prefer not having that attribute in the object if it is not present.

Simply

const obj = Object.assign({}, car);

If car doesn't have battery or fuel, it won't get copied to obj

How to conditionally add attribute to an object?

1 Answers1