Canadian postal code validation

Canadian postal codes can't contain the letters D, F, I, O, Q, or U, and cannot start with W or Z:

[ABCEGHJKLMNPRSTVXY][0-9][ABCEGHJKLMNPRSTVWXYZ][0-9][ABCEGHJKLMNPRSTVWXYZ][0-9]

If you want an optional space in the middle:

[ABCEGHJKLMNPRSTVXY][0-9][ABCEGHJKLMNPRSTVWXYZ] ?[0-9][ABCEGHJKLMNPRSTVWXYZ][0-9]

I suggest the following:

bool FoundMatch = false;
try {
    FoundMatch = Regex.IsMatch(SubjectString, "\\A[ABCEGHJKLMNPRSTVXY]\\d[A-Z] ?\\d[A-Z]\\d\\z");
} catch (ArgumentException ex) {
    // Syntax error in the regular expression
}

Something like this:

^[A-Z]\d[A-Z] \d[A-Z]\d$