Why are the last two console.logs showing false?
const a = 'one';
const b = 'two';
const myArray = [[ 'one', 'two'], ['three', 'four'], ['five', 'six']];
console.log([a, b]);
console.log(myArray[0]);
console.log(myArray.includes([a, b]));
console.log(myArray[0] === [a, b]);in JavaScript arrays and objects are compared by reference and not by value.
One solution I suggest is to use JSON.stringify()
a = ["a", "b"]
b = ["a", "b"]
console.log(JSON.stringify(a) == JSON.stringify(a)) // return trueArray.prototype.includes() and triple equal operator === work with references, they don't compare the elements of the arrays, they compare the array references themselves:
console.log([] === []); // false
const a = [];
const b = a;
console.log(a === b); // trueYou could first convert the array (object) to a string using JSON.stringify(), then compare the string:
const a = 'one';
const b = 'two';
const myArray = [
['one', 'two'],
['three', 'four'],
['five', 'six']
];
console.log(JSON.stringify(myArray[0]) === JSON.stringify([a, b]));You can also run through the separate values using every() and compare them like this:
const a = 'one';
const b = 'two';
const myArray = [[ 'one', 'two'], ['three', 'four'], ['five', 'six']];
const isequal = [a, b].length === myArray[0].length && [a, b].every((value, i) => value === myArray[0][i]);
console.log(isequal);Arrays in JavaScript are Objects and Objects comparison will always return false if the referenced objects aren't the same.
If you want to compare arrays you have to write a function for this or use isEqual func from lodash
