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

Posted by William Mackay
William Mackay
25,189 Points

What Am I Doing Wrong?

How would you select the body element using document.getElementsByTagName, and store it in the variable body?

const body = ?

I thought it would be: const body = document.getElementsByTagName("body");

However, it tells me I'm wrong and I haven't figured a different way. I watched the video again and it looks like that's what he does in the video. Help please!

2 Answers

Joel Bardsley
Joel Bardsley
31,246 Points
Joel Bardsley
Joel Bardsley
31,246 Points

The getElementsByTagName() method returns a collection of all elements in the document with the specified tag name, so you'd have to specify the array key [0] to retrieve the body element itself.

Robert Hemfelt
Robert Hemfelt
7,303 Points
Robert Hemfelt
Robert Hemfelt
7,303 Points

But wouldn't const body = document.getElementsByTagName("body"); return the 'collection' of all elements named 'body,' even if it's only 1 element?

Ben Ahlander
Ben Ahlander
7,528 Points
Ben Ahlander
Ben Ahlander
7,528 Points

so is it

const body = getElementsByTagName('body[0]')

?

Andy Cruz
Andy Cruz
7,846 Points
Andy Cruz
Andy Cruz
7,846 Points

This is the answer:

const body = document.getElementsByTagName('body')[0];

Explanation: First: don't forget that getElementsByClassName is a method of "document", so you have to "call" it. Second: getElementsByTagNam will return a HTML collection of items. So later you'll have to specify the item position. Third: between parentheses, you have to specify only the TagName ('body'). Fourth: finally you have to indicate the position of the item in the array [0].