react setstate documentation code example
Example 1: set state
class App extends React.Component {
state = { count: 0 }
handleIncrement = () => {
this.setState({ count: this.state.count + 1 })
}
handleDecrement = () => {
this.setState({ count: this.state.count - 1 })
}
render() {
return (
<div>
<div>
{this.state.count}
</div>
<button onClick={this.handleIncrement}>Increment by 1</button>
<button onClick={this.handleDecrement}>Decrement by 1</button>
</div>
)
}
}
Example 2: setstate react js
constructor(props) {
super(props);
this.state = {
isActive: true,
};
}
checkStatus = () => {
this.setState({
'isActive' : !this.state.isActive,
});
}
Example 3: setstate in react
Functional Component
const [counter, setCounter] = useState(0);
setCouter(counter + 1);
Example 4: component did mmount
componentDidMount()
Example 5: react.component
class Welcome extends React.Component {
render() {
return <h1>Hello, {this.props.name}</h1>;
}
}
Example 6: component did mmount
componentDidUpdate(prevProps, prevState, snapshot)