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

EDDY saqchez
EDDY saqchez
635 Points
Posted by EDDY saqchez
EDDY saqchez
635 Points

var id = "23188xtr"; var lastName = "Smith"; var userName = 'id'+= '#'+= lastName.toUpperCase()

How do I concate these

app.js 
var id = "23188xtr"; 
var lastName = "Smith";

var userName = 'id'+= '#'+= lastName.toUpperCase()
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>

1 Answer

Matthew Long
Matthew Long
28,407 Points
Matthew Long
Matthew Long
28,407 Points

Looks like you're confused with when to use the addition assignment operator, +=. The addition assignment operator adds the value of the right operand to a variable and assigns the result to the variable. The types of the two operands determine the behavior of the addition assignment operator. Addition or concatenation is possible.

This is how you could use the += operator:

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

var userName = id.toUpperCase();
userName += '#';
userName += lastName.toUpperCase();

This is what the challenge is after, using simple string concatenation:

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

var userName = id.toUpperCase() + '#' + lastName.toUpperCase();

Also, make sure you don't put your variables inside quotations, you don't forget to use the toUpperCase() method, and you don't forget the semicolon!