Text Processing with JavaScript

Recipe 58

Validating Canadian Postal Codes

Task

Let’s suppose you have a specialized shop catering to your Canadian customers, and you want to ensure that the postal code entered by users is a valid Canadian postal code.

In Canada, a postal code is a combination of six characters that includes both letters and digits. The format of the code follows A1A 1A1, where the letter A represents any letter of the alphabet and the number 1 represents any digit. The third and fourth characters are separated by a single space.

For example, the postal code for the CN Tower in Toronto is M5V 1J2. You want to create a regex matching the format of that postal code, but not invalid patterns like A1A 1A1A, 111 111, A1A1A1, A1A-A1A, or 12A 1B1.

Solution

Use the following ...