public static decimal Get(Waehrung from, Waehrung to)
{
// exchange rate is 1:1 for same currency
if (from == to)
{
return(1);
}
var key = string.Format("{0}{1}", from, to); // e.g. EURUSD means "How much is 1 EUR in USD?".
// if we've already downloaded this exchange rate, use the cached value
if (s_rates.ContainsKey(key))
{
return(s_rates[key]);
}
// otherwise create the request URL, ...
var url = string.Format(@"http://download.finance.yahoo.com/d/quotes.csv?s={0}=X&f=sl1d1t1c1ohgv&e=.csv", key);
// download the response as string
var data = new WebClient().DownloadString(url);
// split the string at ','
var parts = data.Split(',');
// convert the exchange rate part to a decimal
var rate = decimal.Parse(parts[1], CultureInfo.InvariantCulture);
s_rates[key] = rate;
return(rate);
}
public void UpdatePrice(decimal newPrice, Waehrung waehrung)
{
if (newPrice < 0)
{
throw new ArgumentException("Preis muss positiv sein.", nameof(newPrice));
}
m_preis = new Preis(newPrice, waehrung);
}
public Preis ConvertTo(Waehrung targetCurrency)
{
if (targetCurrency == Unit)
{
return(this);
}
return(new Preis(Amount * Umrechnung.Get(Unit, targetCurrency), targetCurrency));
}
public Geld(int betrag, Waehrung waehrung)
{
if (!IsValid(betrag, waehrung))
{
throw new InvalidGeldValueException(betrag.ToString());
}
this.Value = betrag;
this.Waehrung = waehrung;
}
public static decimal Get(Waehrung from, Waehrung to)
{
if (from == to)
{
return(1);
}
var key = string.Format("{0}{1}", from, to);
if (s_rates.ContainsKey(key))
{
return(s_rates[key]);
}
var url = string.Format(@"http://download.finance.yahoo.com/d/quotes.csv?s={0}=X&f=sl1d1t1c1ohgv&e=.csv", key);
var data = new WebClient().DownloadString(url);
var parts = data.Split(',');
var rate = decimal.Parse(parts[1], CultureInfo.InvariantCulture);
s_rates[key] = rate;
return(rate);
}
public Bremsen(string produzent, string modell, decimal price, Waehrung waehrung)
: this(produzent, modell, new Preis(price, waehrung))
{
}
public Reifen(string produzent, string modell, decimal preis, Waehrung waehrung)
: this(produzent, modell, new Preis(preis, waehrung))
{
}
public Schaltwerk(string produzent, string modell, decimal price, Waehrung waehrung)
: this(produzent, modell, new Preis(price, waehrung))
{
}
public Preis(decimal amount, Waehrung unit)
{
Amount = amount;
Unit = unit;
}
private bool IsValid(int betrag, Waehrung waehrung) => betrag >= 0 && waehrung != Waehrung.Undefined;