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To remove an event listener in React:

1. useEffectAdd event listeners in the hook .
2. useEffectReturn a function from the hook.
3. When the component unmounts, removeEventListenerremove the event listener using the method.

import {useRef, useEffect} from 'react';

const App = () => {
  const ref = useRef(null);

  useEffect(() => {
    const handleClick = event => {
      console.log('Button clicked');
    };

    const element = ref.current;

    element.addEventListener('click', handleClick);

    // 👇️ remove the event listener when the component unmounts
    return () => {
      element.removeEventListener('click', handleClick);
    };
  }, []);

  return (
    <div>
      <button ref={ref}>Click</button>
    </div>
  );
};

export default App;

useEffectWe added an event listener to an element in the component's hook.

If you want to add an event listener to the window or document object, use the same method but without the ref.

useEffect(() => {
  const handleClick = event => {
    console.log('Button clicked');
  };

  const element = ref.current;

  element.addEventListener('click', handleClick);

  // 👇️ remove the event listener when the component unmounts
  return () => {
    element.removeEventListener('click', handleClick);
  };
}, []);

We pass an empty dependenciesarray to useEffectthe hook, so it will only run when the component mounts.

We only want to call addEventListenerthe method once - when the component mounts.

We store a reference to the element in a variable and use addEventListenerthe method to add a click event listener to the button.

The method takes as its first argument the type of event to listen for, and as its second argument a function to be called when an event of the specified type occurs.

The function we return from the useEffect hook is called when the component unmounts.

return () => {
  element.removeEventListener('click', handleClick);
};

We use removeEventListenerthe method to remove the event listener we registered previously.

The cleanup step is important because we want to make sure that we don't have any memory leaks in our application.

removeEventListenerThe 2 parameters we pass to the method are:

• The event type to remove the event listener for.
• The corresponding event handling function.

Here's a better way to visualize how to remove event listeners in React.

import {useRef, useState, useEffect} from 'react';

const Box = () => {
  const ref = useRef(null);

  useEffect(() => {
    const handleClick = event => {
      console.log('Button clicked');
      console.log('jiyik.com');
    };

    const element = ref.current;

    element.addEventListener('click', handleClick);

    // 👇️ remove the event listener when the component unmounts
    return () => {
      element.removeEventListener('click', handleClick);
      console.log('✅ Event listener removed');
    };
  }, []);

  return (
    <div>
      <button ref={ref}>Click</button>
    </div>
  );
};

const App = () => {
  const [isShown, setIsShown] = useState(true);

  return (
    <div>
      {isShown && <Box />}

      <br />
      <br />

      <button onClick={() => setIsShown(isShown => !isShown)}>
        Toggle box visibility
      </button>
    </div>
  );
};

export default App;

The Box component registers a click event listener that is triggered every time the user clicks the button.

The component's useEffectcleanup hook returns a cleanup function that is run when the component is unmounted.

return () => {
  element.removeEventListener('click', handleClick);
  console.log('✅ Event listener removed');
};

We used a boolean state variable in the App component to render and unmount the Box component.

When the Box component unmounts, an "Event listener removed" message will be logged to the console and the event listener will be removed.