Regular Expression Literals
In this lesson, let's see how regex work in JavaScript.
We'll cover the following...
JavaScript supports regular expressions through the RegExp type and provides a simple syntax to create them, as shown in the Listing below:
Listing: Using RegExp in JavaScript
<!DOCTYPE html>
<html>
<head>
<title>Regular expression literals</title>
<script>
var pattern = /[A-Z]{3}-\d{3}/gi;
var text = "AB-123 DEF-234 ert-456 -34";
console.log(pattern.test(text));
pattern.lastIndex = 0;
var matches;
do {
matches = pattern.exec(text);
console.log(matches);
}
while (matches != null);
</script>
</head>
<body>
Listing 7-5: View the console output
</body>
</html>
📜NOTE: If you are familiar with regular expressions, you can skip this section. If you would like to get more information about using them, I suggest you to start at http://www.regular-expressions.info/quickstart.html.
How it works
The first line of the script (line six) of this short code defines the pattern variable as a regular expression.
var pattern = Ask