JavaScript cheatsheet

Syntax snippets and quick notes for revision.

JS Introduction

const lesson = "JS Introduction";
const checklist = ["understand", "run", "change", "explain"];
console.log(lesson + ": " + checklist.join(" -> "));

Use this js introduction pattern when a JavaScript task needs a small, readable starting point.

const lesson = "Variables";
const checklist = ["understand", "run", "change", "explain"];
console.log(lesson + ": " + checklist.join(" -> "));

Use this variables pattern when a JavaScript task needs a small, readable starting point.

const lesson = "Data Types";
const checklist = ["understand", "run", "change", "explain"];
console.log(lesson + ": " + checklist.join(" -> "));

Use this data types pattern when a JavaScript task needs a small, readable starting point.

const lesson = "Operators";
const checklist = ["understand", "run", "change", "explain"];
console.log(lesson + ": " + checklist.join(" -> "));

Use this operators pattern when a JavaScript task needs a small, readable starting point.

const lesson = "Conditions";
const checklist = ["understand", "run", "change", "explain"];
console.log(lesson + ": " + checklist.join(" -> "));

Use this conditions pattern when a JavaScript task needs a small, readable starting point.

const lesson = "Loops";
const checklist = ["understand", "run", "change", "explain"];
console.log(lesson + ": " + checklist.join(" -> "));

Use this loops pattern when a JavaScript task needs a small, readable starting point.

const lesson = "Functions";
const checklist = ["understand", "run", "change", "explain"];
console.log(lesson + ": " + checklist.join(" -> "));

Use this functions pattern when a JavaScript task needs a small, readable starting point.

const orders = [42, 120, 18, 75];
const largeOrders = orders.filter((total) => total >= 57);
console.log(largeOrders);

Use this arrays pattern when a JavaScript task needs a small, readable starting point.

const customer = { name: "Asha", plan: "Pro", active: true };
console.log(customer.name + " uses " + customer.plan);

Use this objects pattern when a JavaScript task needs a small, readable starting point.

const lesson = "Strings";
const checklist = ["understand", "run", "change", "explain"];
console.log(lesson + ": " + checklist.join(" -> "));

Use this strings pattern when a JavaScript task needs a small, readable starting point.

const button = document.querySelector("#save");
button?.addEventListener("click", () => {
  document.body.dataset.saved = "true";
});

Use this dom pattern when a JavaScript task needs a small, readable starting point.

const button = document.querySelector("#save");
button?.addEventListener("click", () => {
  document.body.dataset.saved = "true";
});

Use this events pattern when a JavaScript task needs a small, readable starting point.