public void GetMaindata()
        {
            if (SortBy == null)
            {
                SortBy = "it.Iserial";
            }

            if (Filter != null)
            {
                Filter = Filter + "it.TblGeneratePurchaseHeader==(@b)";
            }
            else
            {
                ValuesObjects = new Dictionary <string, object>();

                Filter = "it.TblGeneratePurchaseHeader==(@b)";
            }
            ValuesObjects.Add("b", _generatepurchasehaderIserial);
            Loading = true;
            Client.TblGeneratePurchaseHeaderCurrencyAsync(MainRowList.Count, PageSize, SortBy, Filter, ValuesObjects);
        }