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How to merge two arrays in JavaScript

Learn how to merge two arrays together in JavaScript.


Some languages allow you to concatenate arrays using the addition operator, but JavaScript Array objects actually have a method called concat that allows you to take an array, combine it with another array, and return a new array.

var arr1 = [0, 1, 2];
var arr2 = [3, 5, 7];
var primes = arr1.concat(arr2);
// > [0, 1, 2, 3, 5, 7]

As you can see this creates a new array that is the combination of arr1 and arr2. Again, this does not affect either of the original arrays.