Javascript map() method usage

 Sometimes you may need to take an array and apply some logic to its elements so that you get a new array with updated values.

There are multiple ways to achieve this requirement. You may want to do it by creating an empty array, then using .forEach() or a simple .for() to meet your requirement.

Instead of manually iterating over the array using a loop, you can simply use the built-in Array.map() method.

The Array.map() method allows you to iterate over an array and modify its elements using a callback function. The callback function will then be executed on each of the array's elements.

Syntax:

array.map(function(ele, index, array){  }, this);

The callback function() is called on each array element, and the map() method always passes the current element, the index of the current element, and the whole array object to it.

The this argument will be used inside the callback function. By default, its value is undefined .

let users = [
  {firstName : "ram", lastName: "lakshman"},
  {firstName : "our", lastName: "techvillage"},
  {firstName : "java", lastName: "script"}
];
let userFullnames = users.map(function(element){
    return `${element.firstName} ${element.lastName}`;
})
Output:
["ram lakshman", "our techvillage", "java script"]