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forEach() `index` and `array` Parameters
2:04Let's take a look at the forEach() `index` and `array` parameters.
Let me show you just one more thing
about forEach before we move on.
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Let's go the MDN documentation page for
the forEach method.
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You can see here that the callback in
forEach actually accepts some other
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parameters besides the array
element we've been using.
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The second parameter will hold
the index of the current element.
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So if the current value
is the first element, for
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example, the index value will be zero.
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If it's the second element
the index will be one, and so on.
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If your code relies on the position
of the elements in an array,
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this can be helpful to know.
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The third parameter will
hold the whole array itself.
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Neither of these parameters are useful for
most applications, but I just wanted to
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make sure you knew about them in case
you see examples where they're used.
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I'll just demonstrate
the index property quickly.
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Let's say we want to print all
the names in this array here, and
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we want to number them as well.
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I'll just add a second parameter,
the index, to this callback.
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I'll replace this function body
with a call to console.log,
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passing in a template literal.
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Since arrays are zero-based
I'm adding 1 to the index, and
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putting a parenthesis, and then the name.
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I'll delete this console.log
below the loop as well.
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Now when I run this code, You
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can see the index number has been
accessed to provide these numbers.
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One more thing, the index and
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array parameters are available on all of
the array methods we cover in this course.
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If you ever have questions about
what parameters methods accept,
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I recommend checking out MDN for details.
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I've created some additional practice for
you after this video.
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