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

Mustafa Malik
PLUS
Mustafa Malik
Courses Plus Student 1,491 Points
Posted by Mustafa Malik
Mustafa Malik
Courses Plus Student 1,491 Points

There were no guidance on how to use # symbol in javascript.

I know how to concatenate to variables and show them as UpperCase. But don't know where and why to use # sign?

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

Jeff Lemay
Jeff Lemay
14,268 Points
Jeff Lemay
Jeff Lemay
14,268 Points

A '#' is used to target an element with an ID. So, if you have < div id="xample" >, you can target it by using #xample (same as with CSS).