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JavaScript Object-Oriented JavaScript (2015) Constructor Functions and Prototypes Playlist Project

Why pass variable into the array?

I cannot understand why we passed a variable into a array. what will it output and why do it e.g

this.song[this.nowPlayingIndex];

How to put in a understandable way?

1 Answer

Steven Parker
Steven Parker
218,653 Points

The term in brackets is an index into the array, it selects one of the many elements in the array.

So for example, if "this.nowPlayingIndex" has a value of 2 when this expression is evaluated, then the whole thing will have the value of the third item (since index numbers start at 0) of the "song" array inside the object pointed to by "this".