How do you merge two arrays in JavaScript/jQuery?

Method 1: Traditional or simple way – using loop

Iterating on one of two arrays, get each element and append it into the third array.

const arr1 = ['A','B','C','D'];
const arr2 = ['a','b','c','d'];

let arr3 = [];

for(let i = 0,len = arr1.length; i < len; i++){
    arr3[arr3.length] = arr1[i];
    arr3[arr3.length] = arr2[i];
}

console.log(arr3);

Method 2: Using $.merge function

jQuery provides $.merge a function to do this request.

const arr1 = ['A','B','C','D']; 
const arr2 = ['a','b','c','d'];

const arr3 = $.merge(arr1, arr2)

That’s it!