filtering object arrays

Filtering Object Arrays

The filter() method accepts a test function, and returns a new array containing only the elements of the original array that pass the test provided.

 // Suppose we want to get all odd number in an array:
var numbers = [5, 32, 43, 4];

Version ≥ 5.1

var odd = numbers.filter(function(n) { return n % 2 !== 0;
});

Version ≥ 6

let odd = numbers.filter(n => n % 2 !== 0); // can be shortened to (n => n % 2)

odd would contain the following array: [5, 43].

It also works on an array of objects:

var people = [{ id: 1,
  name: "John",
age: 28 }, {
  id: 2,
  name: "Jane",
  age: 31
}, {
id: 3,
  name: "Peter",
age: 55 }];

Version ≥ 5.1

var young = people.filter(function(person) { 
    return person.age < 35;
});

Version ≥ 6

let young = people.filter(person => person.age < 35);

young would contain the following array:

[{
id: 1,
  name: "John",
age: 28 }, {
  id: 2,
  name: "Jane",
  age: 31
}]

You can search in the whole array for a value like this:

var young = people.filter((obj) => { var flag = false; Object.values(obj).forEach((val) => {
if(String(val).indexOf("J") > -1) { flag = true;
return;
} });
if(flag) return obj; });

This returns:

[{
id: 1,
  name: "John",
age: 28 },{
  id: 2,
  name: "Jane",
  age: 31
}]

Filtering Object Arrays​

Filtering Object Arrays