this.setStatereact code example
Example 1: setstate react js
constructor(props) {
super(props);
this.state = {
isActive: true,
};
}
checkStatus = () => {
this.setState({ // use this function
'isActive' : !this.state.isActive,
});
}
Example 2: react setState
incrementCount() {
// Note: this will *not* work as intended.
this.setState({count: this.state.count + 1});
}
handleSomething() {
// Let's say `this.state.count` starts at 0.
this.incrementCount();
this.incrementCount();
this.incrementCount();
// When React re-renders the component, `this.state.count` will be 1, but you expected 3.
// This is because `incrementCount()` function above reads from `this.state.count`,
// but React doesn't update `this.state.count` until the component is re-rendered.
// So `incrementCount()` ends up reading `this.state.count` as 0 every time, and sets it to 1.
// The fix is described below!
}