using System.Text.RegularExpressions;

using System;

​

using static System.Console;

public class Program

{

    public static void Main()

    {

        var sbDados2 = "TARIFA:25/04/2016";

        var match = Regex.Match(sbDados2.ToString(), @"TARIFA:([\d\/]+)");

​

        if (match.Success)

        {

            WriteLine("Sucesso");

        }

    }

}