javascript comparing arrays for equality code example

Example 1: javascript compare arrays

Array.prototype.equals = function(arr2) {
  return (
    this.length === arr2.length &&
    this.every((value, index) => value === arr2[index])
  );
};

[1, 2, 3].equals([1, 2, 3]);	// true
[1, 2, 3].equals([3, 6, 4, 2]);	// false

Example 2: best way compare arrays javascript

// To compare arrays (or any other object):
// Simple Array Example:
const array1 = ['potato', 'banana', 'soup']
const array2 = ['potato', 'orange', 'soup']

array1 === array2;
// Returns false due to referential equality
JSON.stringify(array1) === JSON.stringify(array2);
// Returns true 


// Another Example:
const deepArray1 = [{test: 'dummy'}, [['woo', 'ya'], 'weird']]
const deepArray2 = [{test: 'dummy'}, [['woo', 'ya'], 'weird']]

deepArray1 === deepArray2;
// Returns false due to referential equality
JSON.stringify(deepArray1) === JSON.stringify(deepArray2);
// Returns true

Example 3: check if 2 arrays are equal javascript

var arraysMatch = function (arr1, arr2) {

	// Check if the arrays are the same length
	if (arr1.length !== arr2.length) return false;

	// Check if all items exist and are in the same order
	for (var i = 0; i < arr1.length; i++) {
		if (arr1[i] !== arr2[i]) return false;
	}

	// Otherwise, return true
	return true;

};