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

Posted by dianav
dianav
15,564 Points

why use [i] so many times

I don't understand the logic in this case. Wouldn't be enough calling [i] for the list items only once when we start the event Listener? Why do we have to specify [i] inside the function as well?

1 Answer

Steven Parker
Steven Parker
229,732 Points
Steven Parker
Steven Parker
229,732 Points

A number in braces is an index and does not "call" a function or method as you would with parentheses. And it's a very efficient operation.

It's very common for a loop to establish an index variable (often named "i") which is then used throughout the body code of the loop to access a specific member item in a collection, as is done with the list items in the video example.