public TaxModel[] RetrieveResults(FileHelperModel[] file)
        {
            TaxModel[] domesticList = file.Where(s => s.EmpId.StartsWith("D"))
                .Select(l=> new TaxModel(){DateTime = l.DateTime,Id = l.Id,EmpId = l.EmpId,Invoice = l.Invoice,ServiceTax = 0, EducationalCess = 0, ForeignRemittanceTax = 0})
                .ToArray();

            var groupedQuery =
                domesticList.GroupBy(g => new {month = g.DateTime.Month, year = g.DateTime.Year})
                    .Select(
                        l =>
                            new
                            {
                                Invoice = l.Sum(I => I.Invoice),
                                Date = string.Format("{0}-{1}", l.Key.month, l.Key.year)
                            })
                    .OrderBy(a => a.Date)
                    .ToList();

            domesticList =
                groupedQuery.Select(
                    variable =>
                        new TaxModel()
                        {
                            DateTime = Convert.ToDateTime(variable.Date),
                            Invoice = variable.Invoice,
                            EmpId = null,
                            Id = (int)0,
                            ServiceTax = (int)0,
                            EducationalCess = (int)0
                        }).ToArray();
            return _serviceTax.RetrieveResults(domesticList);
        }
 public void CreateInstance(FileHelperModel[] file)
 {
     var getInternationalInvoice=new GetInternationalInvoice();
     getInternationalInvoice.RetrieveResults(file);
 }