javascript count objects in array of objects without null values

Question

Let's say we have array of objects:

const data = [
  {
    firstName: "Bruce",
    lastName: "Wayne",
    address: "Arkham 6",
    id: "1",
  },
  {
    firstName: "Peter",
    lastName: "Parker",
     address: "LA 54",
    id: "2"
  },
  {
    firstName: "Tony",
    lastName: "Stark",
    address: null,
    id: "3"
  }
];

and want to get length of the array but exclude counting of the objects which has null values (in example above, this is the last object with address property null) so that result of the counting of the example above would be 2.

objectsWithoutNull = data.reduce(function (r, a) {
    return r + +( a!== null);
}, 0);

I'm trying with reduce method, but got 0. Where is the problem in iteration?

do you want to look at a specific property or at all properties? — Nina Scholz
– Nina Scholz, Commented May 22, 2019 at 10:48

Amit Baranes · Accepted Answer · 2019-05-22 10:51:57Z

2

You can filter() the array and than get object values and check where not includes null.

const data = [
  {
    firstName: "Bruce",
    lastName: "Wayne",
    address: "Arkham 6",
    id: "1",
  },
  {
    firstName: "Peter",
    lastName: "Parker",
     address: "LA 54",
    id: "2"
  },
  {
    firstName: "Tony",
    lastName: "Stark",
    address: null,
    id: "3"
  }
];

const notNullable = data.filter(obj=>!Object.values(obj).includes(null));
console.log(notNullable)
console.log(notNullable.length)

More about Object Values Filter Includes

answered May 22, 2019 at 10:51

Amit Baranes

8,1922 gold badges39 silver badges62 bronze badges

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

Comments

Ori Drori · Accepted Answer · 2019-05-22 10:54:51Z

1

Reduce the array, for each object get the values with Object.values(), and check with Array.includes() if it contains a null value. Negate with ! the boolean result of inclues, and use the + operator to convert to number. Add the number to the accumulator.

const data = [{"firstName":"Bruce","lastName":"Wayne","address":"Arkham 6","id":"1"},{"firstName":"Peter","lastName":"Parker","address":"LA 54","id":"2"},{"firstName":"Tony","lastName":"Stark","address":null,"id":"3"}];

const result = data.reduce((r, o) => 
  r + +!Object.values(o).includes(null)
, 0);

console.log(result);

edited May 22, 2019 at 10:54

answered May 22, 2019 at 10:49

Ori Drori

196k32 gold badges243 silver badges233 bronze badges

Comments

Jan · Accepted Answer · 2019-05-22 10:54:09Z

1

An option is to iterate over the object-values of a and test if the value is equal to null. If we found a null don't increase our counter.

const data = [
  {
    firstName: "Bruce",
    lastName: "Wayne",
    address: "Arkham 6",
    id: "1",
  },
  {
    firstName: "Peter",
    lastName: "Parker",
     address: "LA 54",
    id: "2"
  },
  {
    firstName: "Tony",
    lastName: "Stark",
    address: null,
    id: "3"
  }
];

let objectsWithoutNull = data.reduce(function (r, a) {
  let hasNull = false;
  const values = Object.values(a);
  values.map(v => {
    if (v === null) {
      hasNull = true;
    }
  });
  
  return r + !hasNull;
}, 0);

console.log(objectsWithoutNull);

answered May 22, 2019 at 10:54

Jan

2,8532 gold badges23 silver badges26 bronze badges

Comments

Ravikumar Rajendran · Accepted Answer · 2019-05-22 10:57:34Z

1

  objectsWithoutNull = data.reduce(function (r, a) {
        return r + +( Object.values(a).indexOf(null) == -1);
    }, 0);

This will work if you want to check for all the properties!

answered May 22, 2019 at 10:57

Ravikumar Rajendran

5142 silver badges9 bronze badges

Comments

Amir Popovich · Accepted Answer · 2019-05-22 11:01:48Z

1

You can use Array.prototype.every to check that all the values are not null

var length = data.filter(i => Object.values(i).every(i => i !== null)).length

answered May 22, 2019 at 11:01

Amir Popovich

30.1k9 gold badges58 silver badges102 bronze badges

Comments

Andrien Pecson · Accepted Answer · 2019-05-22 13:27:40Z

0

If you are using lodash.

const data = [
      {
        firstName: "Bruce",
        lastName: "Wayne",
        address: "Arkham 6",
        id: "1",
      },
      {
        firstName: "Peter",
        lastName: "Parker",
         address: "LA 54",
        id: "2"
      },
      {
        firstName: "Tony",
        lastName: "Stark",
        address: null,
        id: "3"
      }
    ];

const counter = _.filter(data, ({address}) => {return address != null}).length;
console.log(counter);

answered May 22, 2019 at 13:27

Andrien Pecson

2923 silver badges13 bronze badges

Collectives™ on Stack Overflow

javascript count objects in array of objects without null values

6 Answers 6

Comments

Comments

Comments

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

6 Answers 6

Comments

Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related