You can define default props this way:
export class Counter extends React.Component {
constructor(props) {
super(props);
this.state = {count: props.initialCount};
this.tick = this.tick.bind(this);
}
tick() {
this.setState({count: this.state.count + 1});
}
render() {
return (
<div onClick={this.tick}>
Clicks: {this.state.count}
</div>
);
}
}
Counter.propTypes = { initialCount: React.PropTypes.number };
Counter.defaultProps = { initialCount: 0 };
This is equivalent in TypeScript to defining defaultProps as a static field inside the class body:
class SomeComponent extends Component<IProps, IStates> {
public static defaultProps: IProps = { /* ... */ };
// ...
}