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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Selection Review

selecting 'body' by document.getElementsByTagName

const body = document.getElementsByTagName(body)[0]; is the right anwer for the question ' How do you select the body' by document.getElementsByTagName?' in the quiz. I get it until (body) but what is the purpose of [0] in here. we are just selecting the whole 'body' why don't we just write const body = document.getElementsByTagName(body); and finish the code here?

3 Answers

No, it's storing the body element from the whole HTML Collection

oh i see. thanks for your time. I get it now.

Because document.getElementsbyTagName will return a list of elements and not a single element.

Even if there is only one element with that tag name it will be in a Node List which is why you have to use the [0] to get the particular one.

I recommend open the console of any webpage and type const body = document.getElementsbyTagName('body'); then console.log(body) it will return the whole HTML Collection but if you will const body = document.getElementsbyTagName('body')[0]; and then console.log(body) it will return the exact body element.

i got that but in this 'How would you select the body element using document.getElementsByTagName, and store it in the variable body?

(Hint: Don't forget that this method returns a zero-based collection, not a single element.) question what is zero-based collection mean? does [0] representing the index? if it is why we don't use another index beside 0?

Like this:


It's been stored in const body

so its storing the first body element right?