C#- Validation for US or Canadian zip code

Question

I am using following method to validate US or Canadian zip code, but i think it is not working fine for me. Please suggest me the changes in the regular expression.

private bool IsUSorCanadianZipCode(string zipCode)     {         bool isValidUsOrCanadianZip = false;         string pattern = @"^\d{5}-\d{4}|\d{5}|[A-Z]\d[A-Z] \d[A-Z]\d$";         Regex regex = new Regex(pattern);         return isValidUsOrCanadianZip = regex.IsMatch(zipCode);     } 

Thanks.

Answer 1

    var _usZipRegEx = @"^\d{5}(?:[-\s]\d{4})?$";     var _caZipRegEx = @"^([ABCEGHJKLMNPRSTVXY]\d[ABCEGHJKLMNPRSTVWXYZ])\ {0,1}(\d[ABCEGHJKLMNPRSTVWXYZ]\d)$";      private bool IsUSOrCanadianZipCode(string zipCode)     {         var validZipCode = true;         if ((!Regex.Match(zipCode, _usZipRegEx).Success) && (!Regex.Match(zipCode, _caZipRegEx).Success))         {             validZipCode = false;         }         return validZipCode;     } }