Check if an array contains any element of another array in JavaScript

Vanilla JS

ES2016:

const found = arr1.some(r=> arr2.includes(r))

ES6:

const found = arr1.some(r=> arr2.indexOf(r) >= 0)

How it works

some(..) checks each element of the array against a test function and returns true if any element of the array passes the test function, otherwise, it returns false. indexOf(..) >= 0 and includes(..) both return true if the given argument is present in the array.

vanilla js

/**
 * @description determine if an array contains one or more items from another array.
 * @param {array} haystack the array to search.
 * @param {array} arr the array providing items to check for in the haystack.
 * @return {boolean} true|false if haystack contains at least one item from arr.
 */
var findOne = function (haystack, arr) {
    return arr.some(function (v) {
        return haystack.indexOf(v) >= 0;
    });
};

As noted by @loganfsmyth you can shorten it in ES2016 to

/**
 * @description determine if an array contains one or more items from another array.
 * @param {array} haystack the array to search.
 * @param {array} arr the array providing items to check for in the haystack.
 * @return {boolean} true|false if haystack contains at least one item from arr.
 */
const findOne = (haystack, arr) => {
    return arr.some(v => haystack.includes(v));
};

or simply as arr.some(v => haystack.includes(v));

If you want to determine if the array has all the items from the other array, replace some() to every() or as arr.every(v => haystack.includes(v));

ES6 solution:

let arr1 = [1, 2, 3];
let arr2 = [2, 3];

let isFounded = arr1.some( ai => arr2.includes(ai) );

Unlike of it: Must contains all values.

let allFounded = arr2.every( ai => arr1.includes(ai) );

Hope, will be helpful.

If you're not opposed to using a libray, http://underscorejs.org/ has an intersection method, which can simplify this:

var _ = require('underscore');

var target = [ 'apple', 'orange', 'banana'];
var fruit2 = [ 'apple', 'orange', 'mango'];
var fruit3 = [ 'mango', 'lemon', 'pineapple'];
var fruit4 = [ 'orange', 'lemon', 'grapes'];

console.log(_.intersection(target, fruit2)); //returns [apple, orange]
console.log(_.intersection(target, fruit3)); //returns []
console.log(_.intersection(target, fruit4)); //returns [orange]

The intersection function will return a new array with the items that it matched and if not matches it returns empty array.

ES6 (fastest)

const a = ['a', 'b', 'c'];
const b = ['c', 'a', 'd'];
a.some(v=> b.indexOf(v) !== -1)

ES2016

const a = ['a', 'b', 'c'];
const b = ['c', 'a', 'd'];
a.some(v => b.includes(v));

Underscore

const a = ['a', 'b', 'c'];
const b = ['c', 'a', 'd'];
_.intersection(a, b)

DEMO: https://jsfiddle.net/r257wuv5/

jsPerf: https://jsperf.com/array-contains-any-element-of-another-array

Check if an array contains any element of another array in JavaScript

vanilla js

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