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JavaScript JavaScript and the DOM (Retiring) Responding to User Interaction The Event Object

Phuc Le
Phuc Le
5,182 Points

Event parameter question

In Functions as Parameters video, teacher passed a parameter into the callback function like this:

exec((something) => {
}, 'Hi, there');

something parameter was assigned by string 'Hi, there', but in The Event Object video, event parameter was not assigned by anything, so is event global variable?

1 Answer

Steven Parker
Steven Parker
229,645 Points

The event parameter is passed to the handler by the system.

When an event occurs, the system creates an event object and passes it as a parameter to the event handler.