check if lists have intersection javascript code example

Example 1: js array intersection object

const arr1 = [{ id: 1 }, { id: 2 }]
const arr2 = [{ id: 1 }, { id: 3 }]
const intersection = arr1.filter(item1 => arr2.some(item2 => item1.id === item2.id))
// intersection => [{ id: 1 }]

Example 2: javascript get intersection of two arrays

function getArraysIntersection(a1,a2){
    return  a1.filter(function(n) { return a2.indexOf(n) !== -1;});
}
var colors1 = ["red","blue","green"];
var colors2 = ["red","yellow","blue"];
var intersectingColors=getArraysIntersection(colors1, colors2); //["red", "blue"]