Check out example codes for "react event typescript". It will help you in understanding the concepts better.

Code Example 1

interface IProps_Square {
  message: string;
  onClick: (event: React.MouseEvent<HTMLButtonElement>) => void;
}

Code Example 2

handleChange(e: React.ChangeEvent<HTMLInputElement>) {
    // No longer need to cast to any - hooray for react!
    this.setState({temperature: e.target.value});
  }

  render() {
        ...
        <input value={temperature} onChange={this.handleChange} />
        ...
    );
  }

Code Example 3

onClick={(event: React.MouseEvent<HTMLElement>) => {
 makeMove(ownMark, (event.target as any).index)
}}

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