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JavaScript JavaScript and the DOM (Retiring) Responding to User Interaction Listening for Events with addEventListener()

Posted by Zachary Smith
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Zachary Smith
Full Stack JavaScript Techdegree Graduate 16,616 Points

In "addEventListener('mouseover', (), why are the parentheses empty before the arrow function?

Sorry in advance if this is a ridiculous question but I've understood everything up until now. I did the practice on arrow functions and I thought I understood them but I guess I am struggling to apply their use to methods, particularly the addEventListener method. So what are the first empty set of () supposed to mean? Is this what Guil was referring to as an anonymous function? Thanks in advance.

2 Answers

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

The empty parentheses indicate that the function takes no argument(s), and are required by the syntax.

Arrow function expressions are also anonymous, whether they take arguments or not. That just means they don't have a specific name.

Zachary Smith
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.a{fill-rule:evenodd;}techdegree seal-36
Zachary Smith
Full Stack JavaScript Techdegree Graduate 16,616 Points
Zachary Smith
.a{fill-rule:evenodd;}techdegree seal-36
Zachary Smith
Full Stack JavaScript Techdegree Graduate 16,616 Points

This made more sense once I re-watched the video about events. Thank you.