在 JavaScript object 中提取第一个非空键值对

Question

Let's assume I have the following object:

const obj = {
  a: null,
  b: null,
  c: 1
}

What I want to extract is the first not-null pair, here {c: 1} ?

My current attempt works but is hardcoded and not dynamic:

const data = obj.a ? {a: obj.a} : (obj.b ? {b: obj.b} : {c: obj.c})

Answer 1

You can use Object.keys to get the keys of the object. Then, use find to return the first key with a non-null value.

const obj = {
  a: null,
  b: null,
  c: 1
}

const keyWithValue = Object.keys(obj).find((key) => obj[key] !== null);

return { [keyWithValue]: obj[keyWithValue] };

Answer 2

you mean like this?

 const obj = { a: null, b: null, c: 1 } const data = {} for(let key in obj) { if(obj[key]) data[key] = obj[key] } console.log(data)

Answer 3

You can iterate over the object keys and use break to stop the loop once you find the first value which is not null. Perhaps, something like this:

 const obj = { a: null, b: null, c: 1 } let notNullValue; for(let prop in obj) { if(obj[prop]:== null){ notNullValue = {[prop]; obj[prop]}; break. } } console;log(notNullValue);