Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

JavaScript JavaScript Basics (Retired) Storing and Tracking Information with Variables Using String Methods

Chalenge 2 Task 2

I don't understand the'#' symbol

app.js
var id = "23188xtr";
var lastName = "Smith";
console.log(id.toUpperCase());
var userName = id + lastName;
console.log(lastName.toUpperCase());
var userName = ("id '#' lastName");
index.html
<!DOCTYPE HTML>
<html>
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  <title>JavaScript Basics</title>
</head>
<body>
<script src="app.js"></script>
</body>
</html>

2 Answers

Colin Bell
Colin Bell
29,679 Points

It's just wanting you to concatenate an all uppercase id with a literal # character followed by an all uppercase version of lastName and set it all as the userName variable.

Since you want the values of id and lastName variables, you don't put quotes around them. You do want the actual # character, so you put quotes around it. Use the + sign to concatenate in JavaScript:

var id = "23188xtr";
var lastName = "Smith";

var userName = id.toUpperCase() + "#" + lastName.toUpperCase();
TJ Egan
TJ Egan
14,420 Points

What are you trying to achieve? The # sign is used to denote an 'id'

<div id = "main"><div>

This would be accessed with the # symbol, such as #main