Javascript comparing object

Question

When you comparing object with another object with same property why it returns false?

For Example 
var person={
  age:30

}

var person2={
  age:40

}

console.log(person==person) or console.log(person===person)

it show's in console false why?

Did you mean that `person == person2` returns false? `person == person` will always return true. — Wais Kamal, Sep 26 '18 at 13:57

Benny Powers · Answer 1 · 2018-09-26T13:55:50.017

2

Objects are reference types, which means the equality operators operate on a reference to the object in memory, not to its contents.

In your particular case, you could serialize the object to a string and then check

const compareSerializableObjects = (a, b) =>
  JSON.stringify(a) === JSON.stringify(b)

edited Sep 26 '18 at 13:55

answered Sep 26 '18 at 13:54

Benny Powers

4,693
4
21
46

1

You could also check the individual property that you care about. Those are value types so person.age === person.age – Keith Rousseau Sep 26 '18 at 13:55

score 1 · Answer 2 · answered Sep 26 '18 at 13:59

1

person === person will always return true as you are comparing the same reference, and if you are comparing person === person2 then it is a different refference which is false. Did you mean person.age === person2.age ?

answered Sep 26 '18 at 13:59

Marek Panti

116
9

Javascript comparing object

2 Answers2