How to add properties from this object to another object?

Question

Given

var obj1 = {
  a: \'cat\'
  b: \'dog\'
};
var obj2 = {
  b: \'dragon\'
  c: \'cow\'
};

How can I add properties from obj2 to

Answer 1

Solution:

obj1 = {...obj2, ...obj1};

This solution only works if you know what the expected values might be, e.g. you know they will all be non-empty strings. This uses object spread syntax. You need to ensure that you include obj1 last. You may need a transpiler such as babel until all the browsers (IE...) catch up.

let obj1 = {
  a: 'cat',
  b: 'dog'
};
let obj2 = {
  b: 'dragon',
  c: 'cow'
};
obj1 = {...obj2, ...obj1};
console.log('obj1:', obj1);
console.log('obj2:', obj2);