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

Question

I have a target array [\"apple\",\"banana\",\"orange\"], and I want to check if other arrays contain any one of the target array elements.

For example:

Answer 1

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

Answer 2

const areCommonElements = (arr1, arr2) => {
    const arr2Set = new Set(arr2);
    return arr1.some(el => arr2Set.has(el));
};

Or you can even have a better performance if you first find out which of these two arrays is longer and making Set out for the longest array, while applying some method on the shortest one:

const areCommonElements = (arr1, arr2) => {
    const [shortArr, longArr] = (arr1.length < arr2.length) ? [arr1, arr2] : [arr2, arr1];
    const longArrSet = new Set(longArr);
    return shortArr.some(el => longArrSet.has(el));
};

Answer 3

Just one more solution

var a1 = [1, 2, 3, 4, 5]
var a2 = [2, 4]

Check if a1 contain all element of a2

var result = a1.filter(e => a2.indexOf(e) !== -1).length === a2.length
console.log(result)

Answer 4

My solution applies Array.prototype.some() and Array.prototype.includes() array helpers which do their job pretty efficient as well

ES6

const originalFruits = ["apple","banana","orange"];

const fruits1 = ["apple","banana","pineapple"];

const fruits2 = ["grape", "pineapple"];

const commonFruits = (myFruitsArr, otherFruitsArr) => {
  return myFruitsArr.some(fruit => otherFruitsArr.includes(fruit))
}
console.log(commonFruits(originalFruits, fruits1)) //returns true;
console.log(commonFruits(originalFruits, fruits2)) //returns false;

Answer 5

console.log("searching Array: "+finding_array);
console.log("searching in:"+reference_array);
var check_match_counter = 0;
for (var j = finding_array.length - 1; j >= 0; j--) 
{
    if(reference_array.indexOf(finding_array[j]) > 0)
    {
        check_match_counter = check_match_counter + 1;
    }
}
 var match = (check_match_counter > 0) ? true : false;
console.log("Final result:"+match);

Answer 6

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.