JavaScript map() method in 7 minutes! ๐บ๏ธ
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00:00:00 introduciton
00:00:16 example 1
00:02:13 example 2
00:03:58 example 3
// .map() = accepts a callback and applies that function
// to each element of an array, then return a new array
// ———— EXAMPLE 1 ————
const numbers = [1, 2, 3, 4, 5];
const squared = numbers.map(square);
const cubed = numbers.map(cube);
console.log(cubed);
function square(element){
return Math.pow(element, 2);
}
function cube(element){
return Math.pow(element, 3);
}
// ———— EXAMPLE 2 ————
const students = [“Spongebob”, “Patrick”, “Squidward”, “Sandy”];
const studentsUpper = students.map(upperCase);
const studentsLower = students.map(lowerCase);
console.log(studentsLower);
function upperCase(element){
return element.toUpperCase();
}
function lowerCase(element){
return element.toLowerCase();
}
// ———— EXAMPLE 3 ————
const dates = [“2024-1-10”, “2025-2-20”, “2026-3-30”];
const formattedDates = dates.map(formatDates);
console.log(formattedDates);
function formatDates(element){
const parts = element.split(“-“);
return `${parts[1]}/${parts[2]}/${parts[0]}`;
}