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Andrew Clark
be67db46b6
Adds a second argument to useDeferredValue called initialValue: ```js const value = useDeferredValue(finalValue, initialValue); ``` During the initial render of a component, useDeferredValue will return initialValue. Once that render finishes, it will spawn an additional render to switch to finalValue. This same sequence should occur whenever the hook is hidden and revealed again, i.e. by a Suspense or Activity, though this part is not yet implemented. When initialValue is not provided, useDeferredValue has no effect during initial render, but during an update, it will remain on the previous value, then spawn an additional render to switch to the new value. (This is the same behavior that exists today.) During SSR, initialValue is always used, if provided. This feature is currently behind an experimental flag. We plan to ship it in a non-breaking release.
react-dom
This package serves as the entry point to the DOM and server renderers for React. It is intended to be paired with the generic React package, which is shipped as react to npm.
Installation
npm install react react-dom
Usage
In the browser
import { createRoot } from 'react-dom/client';
function App() {
return <div>Hello World</div>;
}
const root = createRoot(document.getElementById('root'));
root.render(<App />);
On the server
import { renderToPipeableStream } from 'react-dom/server';
function App() {
return <div>Hello World</div>;
}
function handleRequest(res) {
// ... in your server handler ...
const stream = renderToPipeableStream(<App />, {
onShellReady() {
res.statusCode = 200;
res.setHeader('Content-type', 'text/html');
stream.pipe(res);
},
// ...
});
}
API
react-dom
See https://react.dev/reference/react-dom
react-dom/client
See https://react.dev/reference/react-dom/client