what is a hook in react?
A Hook is a special React function that allows functional components to use React features such as state, lifecycle behavior, refs, and context without using class components.
They provide a more direct API to React concepts like props, state, context, refs, and lifecycle.
Before Hooks, state and lifecycle methods could only be used in class components.
Hooks were introduced in React 16.8 to make functional components more powerful.
1.React useState hook:
The react usestate hook allows us to track state in a functional components.
State generally refers to data or properties that need to be tracking in an application.
useState is a React Hook used to store and update data (state) in a functional component.
syntax
const [state, setState] = useState(initialValue);
code
output
three times click button.
How it works
Initial value:
count = 0
When button is clicked:
setCount(count + 1);
Value becomes:
count = 1
count = 2
count = 3
Why use useState?
React updates the screen whenever the state changes.Data changes, React automatically re-renders the component and updates the UI.
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