如何获取另一个对象中不匹配的对象

Question

I have 2 arrays with objects.

const a = [
 {
  name: 'John'
 },
 {
  name: 'Adam'
 }
]

const b = [
 {
  name: 'Adam'
 }
]

I want to get the object is not the same in the array and also get the object that is same in arrays as well.

const same = [
 {
  name: 'Adam'
 }
]

const not_same = [
 {
  name: 'John'
 }
]

Using lodash library is it possible?

Answer 1

You can use intersectionBy and xorBy as follows:

 const a = [{ name: 'John' }, { name: 'Adam' } ]; const b = [{ name: 'Adam' }]; console.log(_.intersectionBy(a, b, 'name')); // values present in both arrays console.log(_.xorBy(a, b, 'name')); // values present in only one of the arrays 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"></script> 

Answer 2

You can use _.partition() to get two arrays according to a certain criteria:

 const a = [{ name: 'John' }, { name: 'Adam' } ]; const b = [{ name: 'Adam' }]; const bMap = _.keyBy(b, 'name'); // create a map of names in b const [same, not_same] = _.partition(a, ({ name }) => name in bMap); // partition according to bMap and destructure into 2 arrays console.log('same: ', same); console.log('not_same: ', not_same); 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.min.js"></script>