Research Documentation - DOM custom events

Define/Explain DOM custom events
DOM custom events are events that you create and control in your code, rather than being predefined by a browser or other platform. These events allow you to create custom event types and trigger them in your code, and then handle them with event listeners. This can be useful for enabling communication between different parts of your code, or for creating more flexible and modular code.

Define/Explain how to create custom events
Use the CustomEvent constructor to create a new custom event object, specifying the name of the event and any options for the event. Trigger the event by calling the dispatchEvent method on the element that you want to trigger the event on, passing the custom event object as an argument. Handle the event by adding an event listener to the element that you want to listen for the event on, using the addEventListener method. This method takes the event name and a callback function as arguments. The callback function will be run whenever the event is triggered, and you can use it to handle the event as needed.

Explain why DOM custom events are used
DOM custom events are used for a variety of reasons, but the main reason is to enable communication between different parts of your code. For example, you might have a piece of code that performs some action, and you want other parts of your code to be notified when that action is completed. In this case, you could use a custom event to trigger a notification when the action is completed, and other parts of your code could listen for that event and take appropriate action.

Summary
In summary, creating and using custom events involves creating the event object, triggering the event, and handling the event with an event listener.