public string this[string columnName]
        {
            get
            {
                switch (columnName)
                {
                case "ApiKey":
                    if (!string.IsNullOrEmpty(ApiKey))
                    {
                        MarketApi marketApi = new MarketApi(ApiKey);
                        try
                        {
                            marketApi.StartPing();
                            var balance = marketApi.GetBalance();

                            KeyIsFinded = "Ключ валидный";
                            Balance     = balance.Result;
                            KeyContorller.SaveKey(ApiKey);
                        }
                        catch
                        {
                            KeyIsFinded = "Ключ не валидный";
                            Balance     = "";
                        }
                        break;
                    }
                    else
                    {
                        var ApiKeyWithFile = KeyContorller.LoadKey();
                        if (string.IsNullOrWhiteSpace(ApiKey))
                        {
                            ApiKey = ApiKeyWithFile;
                        }
                    }
                    break;
                }
                return(_KeyIsFinded);
            }
        }