What is the TypeScript definition for the onMouseOver event in React?

The right interface for onMouseOver is MouseEvent

Please continue reading below to see how to use it or read my guide on using React's events with TypeScript.

Interface

interface MouseEvent<T = Element, E = NativeMouseEvent> extends UIEvent<T, E> {
    altKey: boolean;
    button: number;
    buttons: number;
    clientX: number;
    clientY: number;
    ctrlKey: boolean;
    /**
     * See [DOM Level 3 Events spec](https://www.w3.org/TR/uievents-key/#keys-modifier). for a list of valid (case-sensitive) arguments to this method.
     */
    getModifierState(key: string): boolean;
    metaKey: boolean;
    movementX: number;
    movementY: number;
    pageX: number;
    pageY: number;
    relatedTarget: EventTarget | null;
    screenX: number;
    screenY: number;
    shiftKey: boolean;
}

Full example

import React, { MouseEvent } from 'react';

const ButtonComponent = () => {
  const handleMouseEvent = (e: MouseEvent<HTMLButtonElement>) => {
    e.preventDefault();
    // Do something
  };

  return <button onMouseOver={handleMouseEvent}>Click me!</button>;
};

export default ButtonComponent;

Attributes that use MouseEvent: