public ExchangeController(IMemoryCache memorycache, ILogger <ExchangeController> logger) { _exchange_service = new ExchangeService(); _cache = memorycache; _logger = logger; _exchange_service.GetExchangeInfo(); List <ExchangeInfo> list = _exchange_service.GetList(); foreach (var item in list) { _cache.Set(item.Currency, item, TimeSpan.FromDays(1)); } }