public static async Task <ApiForexRates> GetRate(string key = null, string format = "proto", string from = "USD", string[] to = null, DateTime?date = null)
{
string CurrencyToConvert = string.Empty;
if (to != null)
{
CurrencyToConvert = string.Join(",", to);
}
ApiForexRates ApiForexRates = new ApiForexRates();
using (HttpClient client = new HttpClient())
using (HttpResponseMessage response = await client.GetAsync(BaseUri + "daily-rates." + format + "?from=" + from + "&to=" + CurrencyToConvert + "&key=" + key))
using (HttpContent content = response.Content)
switch (format)
{
case "proto":
using (var memoryStream = new MemoryStream())
{
await content.CopyToAsync(memoryStream);
memoryStream.Seek(0, SeekOrigin.Begin);
ApiForexRates = Serializer.Deserialize <ApiForexRates>(memoryStream);
}
break;
case "json":
ApiForexRates = JsonConvert.DeserializeObject <ApiForexRates>(await content.ReadAsStringAsync());
break;
}
return(ApiForexRates);
}
public static decimal Convert(this ApiForexRates DailyRates, string from, string to, decimal ammount = 1)
{
decimal rateFrom = DailyRates.rates.Where(r => r.Key == from).Select(r => r.Value).First();
decimal rateTo = DailyRates.rates.Where(r => r.Key == to).Select(r => r.Value).First();
return(rateFrom / rateTo * ammount);
}
private async Task GetRatesAsync()
{
if ((DateTime.UtcNow - _lastFetchedAt).TotalDays > Constants.DEFAULTDAYSPERRATEREFRESH)
{
_rates = await ApiForex.GetRate(_apiKey);
_lastFetchedAt = DateTime.UtcNow;
}
}