Javascript Arrays - Checking two arrays of objects for same contents, ignoring order

With ES6 you could use every and some (and length).

let A = [1, 2, 3]; let B = [2, 3, 1]; // all objects in A are contained in B (A ⊆ B) // you can compare a <-> b however you'd like (here just `a === b`) let AsubB = A.every(a => B.some(b => a === b)); // A and B are the same length let sameLength = A.length === B.length; // their contents are as equal as previously tested: let equal = AsubB && sameLength; 

This is probably the simplest method if not the slowest.

var o = { PropA: 1, PropB: 2 }; var a = [1, 2, 3, 4, o]; var b = [2, 3, 4, 1]; var c = a.filter(function(value, index, obj) { return b.indexOf(value) > -1; }); if (c.length !== a.length) { throw new Error("Array b is missing some elements!"); } 

indexOf will only check that they refer to the same object. If you want to check value equivalence you will have to do a deep compare of the properties or use JSON.stringify as you mention in your question.

developing/writing code block is fine and this needs deep comparision. but as a developer, we don't need to write code from scratch. we have plenty of options. We are also having a huge npm packages to get the job done specifically developed for these use case. I have used similar-js" it did the job that you need. It extends so many use cases as well.

https://www.npmjs.com/package/similar-js

npm i similar-js

import {isSimilar} from 'similar-js'; const a = [ { id: 0, name: "Ashley Lyons", }, { id: 1, name: "Ophelia Erickson", }, { id: 2, name: "Britney Cook", }, ] const b = [ { id: 2, name: "Britney Cook", }, { id: 0, name: "Ashley Lyons", }, { id: 1, name: "Ophelia Erickson", }, ] console.log(isSimilar(a, b)) 

(Disclosure: I am the owner of the linked repo)

Simple & Elegant

function isEqual(arr1, arr2) { if (arr1.length !== arr2.length) return false; return arr1.every(x => arr2.includes(x)); } 

If duplication is important, use this

function isEqual(arr1, arr2) { if (arr1.length !== arr2.length) return false; arr1.sort(); arr2.sort(); for (var i = 0; i < arr1.length; i++) { if (arr1[i] !== arr2[i]) return false; } return true; } 

Hi it seem more difficult than I thought and I need to code it myself. Please check my solution:

//usage const arr1 = [{ a: 1, b: 2 }, { a: 2, b: 1 }, { a: 1, b: 2, c: 3 }, ]; const arr2 = [{ a: 1, b: 2, c: 3 }, { a: 1, b: 2 }, { a: 2, b: 1 }, ]; alert(compareTwoArray(arr1, arr2)); function compareTwoArray(arr1, arr2) { if (arr1.length != arr2.length || arr1.length == arr2.length == 0) { return false; } //clone arr to process let arr01 = JSON.parse(JSON.stringify(arr1)); let arr02 = JSON.parse(JSON.stringify(arr2)); for (let i = (arr01.length - 1); i >= 0; i--) { for (let j = (arr02.length - 1); j >= 0; j--) { if (JSON.stringify(arr01[i]) === JSON.stringify(arr02[j])) { arr01.splice(i, 1); arr02.splice(j, 1); } } } if (arr01.length == 0 && arr02.length == 0) { return true; } else { return false; } }

This is for array of values only:

//usage alert(compareTwoArray([0, 0, 1, 1], [1, 0, 1, 0])); function compareTwoArray(arr1, arr2) { if (arr1.length != arr2.length || arr1.length == arr2.length == 0) { return false; } //clone arr to process let arr01 = JSON.parse(JSON.stringify(arr1)); let arr02 = JSON.parse(JSON.stringify(arr2)); for (let i = (arr01.length - 1); i >= 0; i--) { for (let j = (arr01.length - 1); j >= 0; j--) { if (arr01[i] == arr02[j]) { //remove duplicate item from both array arr01.splice(i, 1); arr02.splice(j, 1); } } } if (arr01.length == 0 && arr02.length == 0) { return true; } else { return false; } }