ParseEx.cs

public static class ParseEx {
  public delegate bool ParserDelegate<T>(string input, out T result);

  public static Maybe<T> Parse<T>(string input, ParserDelegate<T> parser) {
    T result;
    bool isSuccess = parser(input, out result);
    return isSuccess ? result.ToMaybe() : new Nothing<T>();
  }

  public static Maybe<DateTime> ParseDateTime(string input) {
    return Parse<DateTime>(input, DateTime.TryParse);
  }

  public static Maybe<int> ParseInt32(string input) {
    return Parse<int>(input, Int32.TryParse);
  }
}

Use with https://gist.github.com/rarous/5355792