How to remove key and value undefined in object?

Question

how to remove key and value that are undefined from object?

for example I have

var x = {
 firstname: undefined,
 lastname: 'blabla'
}

how to get object without undefined? in the most efficient and quick way?

the result should be:

x = {
 lastname: 'blabla'
}

Possible duplicate of [Javascript - removing undefined fields from an object](https://stackoverflow.com/questions/25421233/javascript-removing-undefined-fields-from-an-object) and [Remove blank attributes from an Object in Javascript](https://stackoverflow.com/questions/286141) — adiga, May 22 '19 at 15:02

score 1 · Accepted Answer · answered May 22 '19 at 14:57

1

var x = {
 firstname: undefined,
 lastname: 'blabla'
}

for (let key in x) {
  if (x[key] === undefined) {
   delete x[key];
  }
}

answered May 22 '19 at 14:57

Muhammad Usman

1 Answers1