React Cheat Sheet
|
This section documents React 19.x for the web, using function components and Hooks throughout (class components appear only where React still requires them, such as error boundaries). React Native is out of scope and gets only a pointer. The React 19 additions follow the current official React documentation. This content was generated with the assistance of AI and should be verified against react.dev before being relied on in production, since React APIs continue to evolve between releases. This section’s bibliography lists the reference material consulted while preparing these pages. |
A single-page, colour-coded summary of the React 19 essentials — the createRoot entry point, JSX rules, a
function component with props, useState / useReducer, useEffect with cleanup, useContext, useRef,
memo / useMemo / useCallback, event handling, lists and keys, conditional rendering, lazy
<Suspense>, a custom-Hook skeleton, the Rules of Hooks and of React, and the React 19 use and Actions APIs — handy for quick memorization or as a printable desk reference.
For the full explanation, every option, and additional examples, see the dedicated pages:
Fundamentals — Getting Started with React, JSX and Rendering, Components and Props, and State and Events.
Hooks & effects — Core Hooks and the Rules of Hooks, Effects and Lifecycle, and Custom Hooks.
State, performance & Suspense — State Management, Performance and Concurrent Features, and Code Splitting and Suspense.
Forms, routing & data — Forms and Actions, Routing, Data Fetching, and Refs and the DOM.
TypeScript & testing — TypeScript with React and Testing.
Rendering, build & delivery — Server Rendering, SSG and React Server Components, Build and Deployment, and Styling and UI Libraries.
Reference — The Rules of React.