Regular Expression for Canadian Postal Code to also allow for lowercase letters or a dash after the first three characters

Question

^[ABCEGHJ-NPRSTVXY]{1}[0-9]{1}[ABCEGHJ-NPRSTV-Z]{1}[ ]?[0-9]{1}[ABCEGHJ-NPRSTV-Z]{1}[0-9]{1}$

I would like to add lower case characters to this regex (currently only capital letters are allowed). I would also like the separator in the middle: '[ ]?' to also allow for a dash (currently allows a space or no space). How do I ammend the above regex to account for these possible variations. Language being used is .net.

Answer 1

When you use the regular expression constructor, pass the RegexOptions.IgnoreCase flag .

For the second requirement, change [ ]? to [ -]? .

Summary:

var regex = new Regex(@"^[ABCEGHJ-NPRSTVXY]{1}[0-9]{1}[ABCEGHJ-NPRSTV-Z]{1}[ -]?[0-9]{1}[ABCEGHJ-NPRSTV-Z]{1}[0-9]{1}$", RegexOptions.IgnoreCase);