Asynchronous rendering via React.Suspense
Asynchronous rendering via React.Suspense
React.Suspense Explained
React.Suspense
is a component in React that allows you to handle asynchronous rendering in a declarative way. It is primarily used for code splitting (lazy loading) and handling asynchronous data fetching in modern React applications.
When to Use React.Suspense
You should use React.Suspense
when:
-
Lazy Loading Components – When you dynamically import a component using
React.lazy()
,React.Suspense
provides a fallback UI while the component loads. -
Data Fetching with React Server Components – In React 18+,
Suspense
is used to defer rendering until data is available. -
Streaming Server-Side Rendering (SSR) – Helps optimize the hydration process in server-rendered applications.
Example Use Cases
1. Lazy Loading Components
This is useful for reducing bundle size and improving performance.
👉 Here, LazyComponent
is loaded asynchronously, and while it is being fetched, "Loading..."
is displayed.
2. Handling Async Data Fetching (React 18)
With React 18 concurrent features, you can use Suspense
for data fetching.
👉 This will delay rendering UserProfile
until fetchUserData
resolves.
Key Takeaways
-
Suspense
is not for handling regular Promises; it's mainly for integration withReact.lazy
or concurrent React features like React Server Components. -
It allows you to show a fallback UI while waiting for async resources.
-
In React 18, it improves SSR and concurrent rendering performance.
Would you like more advanced examples or integration with libraries like React Query? 🚀