Iterate through each item in an array, transform it, and return a new array. The callback accepts three arguments: the current item in the loop’s value, its index, and the array itself.
/**
* Double each number in an array
*/
var numbers = [1, 4, 9];
var doubles = numbers.map(function(num) {
return num * 2;
});
// logs [2, 8, 18]
console.log(doubles);
/**
* Get an array of just names
*/
var data = [
{
name: 'Kyle',
occupation: 'Fashion Designer'
},
{
name: 'Liza',
occupation: 'Web Developer'
},
{
name: 'Emily',
occupation: 'Web Designer'
},
{
name: 'Melissa',
occupation: 'Fashion Designer'
},
{
name: 'Tom',
occupation: 'Web Developer'
}
];
var names = data.map(function (item) {
return item.name;
});
// logs ["Kyle", "Liza", "Emily", "Melissa", "Tom"]
console.log(names);