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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Select All Elements of a Particular Type

Posted by Nelson J
Nelson J
7,411 Points

isn't selecting the li tag inside the ul tag, the same as selecting the elements inside an array, if so, why it loops?

This is what I mean:

/* Selects li and loops over it,
yet, it doesn't have lis inside
*/
const myList = document.getElementsByTagName('li');


/* Should be used 
because ul actually has the lis inside
*/
const myList = document.getElementsByTagName('ul');

I used the ul and it works the same. confusing.

1 Answer

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

When you select something by tag name, you are referencing that item and not its contents. But you could get the items inside by using the "children" property. Also remember that "getElementsByTagName" returns a collection, even if it only contains one thing.

const myList = document.getElementsByTagName('li');  // the collection of all "li" elements
const myList = document.getElementsByTagName('ul')[0].children;  // the same, "the hard way"

Note that these only do the same thing when there is only one ul on the page. Otherwise, the first still gets all li elements on the page, but the second only gets the ones inside the first ul.