Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript Interactive Web Pages with JavaScript Selecting Elements and Adding Events with JavaScript Selecting Elements

Pablo Grippo
Pablo Grippo
25,765 Points
Posted by Pablo Grippo
Pablo Grippo
25,765 Points

I have a problem for selecting an element in JS.

I write this code:

var lastName = document.getElementsByTagName("last_name")[1];

for select the second span element, but it throws me an error. WHY?

app.js 
var fullName = document.getElementById("full_name");
var lastName = document.getElementsByTagName("last_name")[1];
index.html 
<!DOCTYPE html>
<html>
<head></head>
<body>
<h1 id="full_name"><span class="first_name">Andrew</span> <span class="last_name">Chalkley</span></h1>

<script src="app.js"></script>
</body>
</html>

2 Answers

William Li
PLUS
William Li
Courses Plus Student 26,868 Points
William Li
William Li
Courses Plus Student 26,868 Points

Your select a wrong element. getElementsByTagName should target span, not last_name.

Select the second SPAN element on the page

var lastName = document.getElementsByTagName("span")[1];
Pablo Grippo
Pablo Grippo
25,765 Points
Pablo Grippo
Pablo Grippo
25,765 Points

It works! Thank you so much William Li!

Fred Sites
Fred Sites
11,151 Points
Fred Sites
Fred Sites
11,151 Points

What's the error?

Yea William is right. You could alternatively leave the class name and do getElementByClassName