问题
I am developing a stationery program. Customers have choice to pick their region either US or Canada. When they enter address they have to enter ZIP/Postal code. I am trying to validate field but I cannot use reg exp either for US or Canada. I require a regular expression that validates for both country zip code.
回答1:
Not knowing what language you're using, I will not use any abbreviations for character classes:
^[0-9]{5}$|^[A-Z][0-9][A-Z] ?[0-9][A-Z][0-9]$
Depending on your language, you might be able to abbreviate this to
^([0-9]{5}|[A-Z][0-9][A-Z] ?[0-9][A-Z][0-9])$
or
^(\d{5}|[A-Z]\d[A-Z] ?\d[A-Z]\d)$
To support ZIP+4:
^(\d{5}(-\d{4})?|[A-Z]\d[A-Z] ?\d[A-Z]\d)$
And if you want to get really picky about your Canada codes:
^(\d{5}(-\d{4})?|[A-CEGHJ-NPRSTVXY]\d[A-CEGHJ-NPRSTV-Z] ?\d[A-CEGHJ-NPRSTV-Z]\d)$
回答2:
Furthering the answer above you could add (?i) to the beginning of the regex to make is case insensitive. So it would look like this:
^(?i)(\d{5}(-\d{4})?|[A-CEGHJ-NPRSTVXY]\d[A-CEGHJ-NPRSTV-Z] ?\d[A-CEGHJ-NPRSTV-Z]\d)$
来源：https://stackoverflow.com/questions/22545097/one-regular-expression-to-validate-us-and-canada-zip-postal-code