setState method 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: lifecycle method react
INITIALIZATION= setup props and state
MOUNTING= constructor->componentWillMount->render->componentDidMount
UPDATE= shouldComponentUpdate->componentWillUpdate->render
->componentDidUpdate
UNMOUNTING= componentWillUnmount
Example 4: setstate in react
Functional Component
const [counter, setCounter] = useState(0);
setCouter(counter + 1);
Example 5: react setState
this.setState({
date: new Date()
});
Example 6: react setState
incrementCount() {
this.setState({count: this.state.count + 1});
}
handleSomething() {
this.incrementCount();
this.incrementCount();
this.incrementCount();
}