private decimal CalculateExchangeRate(string symbol) { var firstChars = symbol.Substring(0, 3); switch (firstChars) { case "USD": return(ExchangeRates.GetUsd()); case "GOL": return(ExchangeRates.GetUsd()); case "AUD": return(ExchangeRates.GetAud()); case "JPY": return(ExchangeRates.GetJpy()); case "NZD": return(ExchangeRates.GetNzd()); case "EUR": return(ExchangeRates.GetEur()); case "GBP": return(ExchangeRates.GetGbp()); case "CHF": return(ExchangeRates.GetChf()); case "CAD": return(ExchangeRates.GetCad()); case "PLN": return(1); default: Console.WriteLine("nieznana waluta"); return(0); } }