Filtering array of objects based on array

Question

I am trying to filter one array of objects that looks like this

const ELEMENT_DATA: PeriodicElement[] = [
  { position: 1, name: 'Hydrogen', weight: 1.0079, symbol: 'H' },
  { position: 2, name: 'Helium', weight: 4.0026, symbol: 'He' },
  { position: 3, name: 'Lithium', weight: 6.941, symbol: 'Li' },
  { position: 4, name: 'Beryllium', weight: 9.0122, symbol: 'Be' },
  { position: 5, name: 'Boron', weight: 10.811, symbol: 'B' }
];

And an array that looks like this

const values = [1,5];

What I need is to filter ELEMENT_DATA to NEW_VALUES look like this

const NEW_VALUES: PeriodicElement[] = [
  { position: 1, name: 'Hydrogen', weight: 1.0079, symbol: 'H' },
  { position: 5, name: 'Boron', weight: 10.811, symbol: 'B' }
];

I have tried with filter like this:

  filterData(locationName: any) {
    return ELEMENT_DATA.filter(object => {
      return object.position === locationName;
    });
  }

but always I get an empty array.

Is locationName your array of numbers? If so 1. why type it as any? And 2. Did you think e.g. 1 === [1, 5]?! — jonrsharpe
– jonrsharpe, Commented Jan 17, 2020 at 7:55

iY1NQ · Accepted Answer · 2020-01-17 07:53:20Z

2

If the locationName gets as input [1,5] then the code should look like this:

 filterData(locationName: number[]) {
    return ELEMENT_DATA.filter(object => {
      return locationName.includes(object.position);
    });
  }

answered Jan 17, 2020 at 7:53

iY1NQ

2,53418 silver badges19 bronze badges

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

Comments

Sohan · Accepted Answer · 2020-01-17 08:06:24Z

0

You can use Array.prototype.filter()

ELEMENT_DATA.filter(function (object) {
  return locationName.indexOf(object.position) !== -1; // -1 means not present
});

or with underscore JS , using the same predicate:

_.filter(ELEMENT_DATA, function (object) {
  return locationName.indexOf(object.position) !== -1; // -1 means not present
}

If you have access to ES6 collections or a polyfill for Set. Here locationName should be a type of Set

ELEMENT_DATA.filter(object=> locationName.has(object.position))

answered Jan 17, 2020 at 8:06

Sohan

6,8796 gold badges40 silver badges59 bronze badges

Collectives™ on Stack Overflow

Filtering array of objects based on array

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related