TypeError: undefined is not an object after Sorting an array?

Question

I have an array with different objects and they have different date fields that i want to sort regardless of the property name created_at, order_date or updated_at. How can i sort the array by the nearest date to today's date ? The problem is i have order_date is inside another object and when i try to sort i'm having this error message

TypeError: undefined is not an object b.orderInformation.order.order_date`

const array = [
  { type : 'type1', created_at: '2021-07-31' },
  {
    type : 'type2',
    orderInformation: { order: { order_date: '2021-07-13' } }
  },
  {
    type : 'type2',
    orderInformation: { order: { order_date: '2021-07-07' } }
  },
  { type : 'type1', created_at: '2021-08-05' },
  { type : 'type3', updated_at: '2021-09-05' }
];

const res = array.sort(function(a, b) {
  return new Date(b.orderInformation.order.order_date ?? b.created_at ?? b.updated_at) - new Date(a.orderInformation.order.order_date ?? a.created_at ?? a.updated_at);
})

orderInformation is undefined in the first element of the array (it doesn't exists) — Ariel
– Ariel, Commented Jul 16, 2021 at 13:45
Yes, that's why you are getting the error. you'll need to check if the object has the property you are expecting — Ariel
– Ariel, Commented Jul 16, 2021 at 13:50

andy mccullough · Accepted Answer · 2021-07-16 13:53:19Z

2

you'll need to use the optional chaining operator to allow for gracefully handling properties that don't exist on your objects -

a.orderInformation?.order?.order_date

and

b.orderInformation?.order?.order_date

const array = [
  { type : 'type1', created_at: '2021-07-31' },
  {
    type : 'type2',
    orderInformation: { order: { order_date: '2021-07-13' } }
  },
  {
    type : 'type2',
    orderInformation: { order: { order_date: '2021-07-07' } }
  },
  { type : 'type1', created_at: '2021-08-05' },
  { type : 'type3', updated_at: '2021-09-05' }
];

const res = array.sort(function(a, b) {
  return new Date(b.orderInformation?.order?.order_date ?? b.created_at ?? b.updated_at) - new Date(a.orderInformation?.order?.order_date ?? a.created_at ?? a.updated_at);
})

console.log(res)

edited Jul 16, 2021 at 13:53

answered Jul 16, 2021 at 13:46

andy mccullough

9,6817 gold badges38 silver badges64 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Andreas Over a year ago

But is this really a question and/or answer that will help future readers? Check the existence before you use it?

andy mccullough Over a year ago

@Andreas, no need on created_at and updated_at, they are strings, not objects

Collectives™ on Stack Overflow

TypeError: undefined is not an object after Sorting an array?

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related