How Can I Pass Arguments to JavaScript Event Listeners?

Passing Arguments to EventListener Listener Functions

In scenarios where you need to pass arguments to listener functions within addEventListener calls, the value of the argument may not be accessible within the listener. This is because the function is treated as a new variable within the listener's scope.

Solution: Utilizing the target Attribute

To resolve this issue, consider using the target attribute of the event object within the listener function. By setting a custom property on the event target, you can access the desired argument within the listener.

Example:

Consider an HTML button and a JavaScript event listener:

<button>

const myButton = document.getElementById('myButton');

// Set a custom property on the button target
myButton.myParam = 'This is my parameter';

// Add an event listener to the button
myButton.addEventListener('click', (event) => {
  // Retrieve the custom property from the event target
  const myParameter = event.currentTarget.myParam;

  // Do something with the parameter
  alert(`My parameter: ${myParameter}`);
});

In this example, when the button is clicked, the value of the myParam property is retrieved from the event target and displayed in an alert. This approach allows you to pass arguments to listener functions effectively and access them within the listener's scope.

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