Regular expression for Dutch zip / postal code

Question

I\'m trying to build a regular expression in javascript to validate a Dutch zipcode.

The zipcode should contain 4 numbers, then optionally a space and then 2 (case insen

Answer 1

Here is my solution. The i in the end makes it case-insensitive:

var rege = /^\d{4} ?[a-z]{2}$/i;