private int getTaxDeclaration(int comId, string pattern, string serial, string invNo) { int result = -2; IPublishInvoiceService PubIn = IoC.Resolve <IPublishInvoiceService>(); string latestTaxDeclarationDate = PubIn.GetLatestTaxDeclarationDate(); if (latestTaxDeclarationDate != null) { string createDateByFKey = PubIn.GetArisingDateByinvNo(comId, pattern, serial, invNo); DateTime latestTaxDeclarationDateTime = System.Convert.ToDateTime(latestTaxDeclarationDate); DateTime createDateFKey = System.Convert.ToDateTime(createDateByFKey); result = DateTime.Compare(createDateFKey, latestTaxDeclarationDateTime); } return(result); }