Add useUpdate

snippets/useUpdate.md

@@ -0,0 +1,31 @@
+---
+title: useUpdate
+tags: components,reducer,beginner
+firstSeen: 2021-09-24T05:00:00-04:00
+---
+
+Forces the component to re-render when called.
+
+- Use the `useReducer()` hook that creates a new object every time it's updated and return its dispatch.
+
+```jsx
+const useUpdate = () => {
+  const [, update] = React.useReducer(() => ({}));
+  return update;
+};
+```
+
+```jsx
+const MyApp = () => {
+  const update = useUpdate();
+
+  return (
+    <>
+      <div>Time: {Date.now()}</div>
+      <button onClick={update}>Update</button>
+    </>
+  );
+};
+
+ReactDOM.render(<MyApp />, document.getElementById('root'));
+```