我已经移交了一个使用实体框架的应用程序。我对实体并不熟悉，而且我遇到了一个我无法弄清楚的问题。此应用程序用于将数据从数据库迁移到更多关系数据库。在初始迁移之后，我们必须再次运行它以插入不属于原始迁移的其他行。 （有3周的差距）。我知道我必须办理登机手续，我想通过我们使用的一个名为＆＃34; DateChanged＆＃34;但不幸的是，我不确定如何在实体中做到这一点。这是我的第一次努力，只是用红色表示令人沮丧。我在互联网上搜索但没有找到解决方案。
if (!newData.tVehicleLogs.Any(v => v.DateChanged.Value.ToShortDateString("6/27/2014")))//I'm not sure how to check the DateChanged here.
{
newData.tVehicleLogs.Add(deal);
comment = new tVehicleComment
{
Comment = vehicle.Reason,
DealID = deal.DealID,
CurrentComment = false
};
newData.tVehicleComments.Add(comment);
newData.SaveChanges();
int cId = comment.CommentID;
deal.CommentID = cId;
}
}
因为你可以看到我试图用if语句检查日期，但是我无法在尝试所有我知道的尝试之后获得正确的语法...这不是＆＃39在这一点上。
我基本上需要检查DateChanged是否从2014年6月27日到今天的日期。如果在此之前，它已经迁移过，并且不需要再次迁移。如果该行是注释，如果该行是新的，则它将旧注释插入新注释表中，然后使用commentID更新tVehicleLogs表。我只是坚持日期检查部分。非常感谢任何帮助!!
编辑：这是插入tVehicleLogs的整个代码..
if (MigrateLogs)
{
List<VLog> vlog = oldData.VLogs.ToList();
foreach (VLog vehicle in vlog)
{
tBank bank;
tCustomer cust;
tFIManager manag;
tSalesPerson sales;
tMake make;
tModel model;
tDealership dealership;
tMakeDealership makedeal;
tVehicleComment comment;
tInternalLocation location;
string dealershipName = getProperDealershipName(vehicle.Dealership, newData);
bank = (newData.tBanks.Any(banks => banks.BankName == vehicle.BankName) ? newData.tBanks.Where(b => b.BankName == vehicle.BankName).FirstOrDefault() : newData.tBanks.Add(new tBank { BankName = vehicle.BankName }));
cust = (newData.tCustomers.Any(customer => customer.CustomerNumber == vehicle.CustNumber) ? newData.tCustomers.Where(customer => customer.CustomerNumber == vehicle.CustNumber).FirstOrDefault() : newData.tCustomers.Add(new tCustomer { CustomerNumber = vehicle.CustNumber, CustomerName = vehicle.Buyer }));
//cust = (newData.tCustomers.Any(customer => customer.CustomerNumber == vehicle.CustNumber && customer.CustomerName == vehicle.CustNumber) ? newData.tCustomers.Where(customer => customer.CustomerNumber == vehicle.CustNumber).FirstOrDefault() : newData.tCustomers.Add(new tCustomer { CustomerNumber = vehicle.CustNumber, CustomerName = vehicle.Buyer }));
manag = (newData.tFIManagers.Any(manager => manager.FIName == vehicle.FIName) ? newData.tFIManagers.Where(manager => manager.FIName == vehicle.FIName).FirstOrDefault() : newData.tFIManagers.Add(new tFIManager { FIName = vehicle.FIName }));
sales = (newData.tSalesPersons.Any(person => person.SalesPersonNumber == vehicle.SalesPerson) ? newData.tSalesPersons.Where(person => person.SalesPersonNumber == vehicle.SalesPerson).FirstOrDefault() : newData.tSalesPersons.Add(new tSalesPerson { SalesPersonNumber = vehicle.SalesPerson }));
make = (newData.tMakes.Any(m => m.Make == vehicle.Make) ? newData.tMakes.Where(m => m.Make == vehicle.Make).FirstOrDefault() : newData.tMakes.Add(new tMake { Make = vehicle.Make }));
model = (newData.tModels.Any(m => m.Model == vehicle.Model) ? newData.tModels.Where(m => m.Model == vehicle.Model).FirstOrDefault() : newData.tModels.Add(new tModel { Model = vehicle.Model, MakeID = make.MakeID }));
dealership = (newData.tDealerships.Any(d => d.DealershipName == dealershipName) ? newData.tDealerships.Where(d => d.DealershipName == dealershipName).FirstOrDefault() : newData.tDealerships.Add(new tDealership { DealershipName = dealershipName }));
makedeal = (newData.tMakeDealerships.Any(d => d.MakeID == make.MakeID && d.DealershipID == dealership.DealershipID) ? newData.tMakeDealerships.Where(d => d.MakeID == make.MakeID && d.DealershipID == dealership.DealershipID).FirstOrDefault() : newData.tMakeDealerships.Add(new tMakeDealership { DealershipID = dealership.DealershipID, MakeID = make.MakeID }));
location = (newData.tInternalLocations.Any(l => l.LocationName == vehicle.Location) ? newData.tInternalLocations.Where(l => l.LocationName == vehicle.Location).FirstOrDefault() : newData.tInternalLocations.Add(new tInternalLocation { LocationName = vehicle.Location }));
//log = (newData.tVehicleLogs.Any(l => l.DealNumber == vehicle.FIMAST &&) ? newData.tVehicleLogs.Where(l => l.DealNumber == vehicle.FIMAST).FirstOrDefault() : newData.tVehicleLogs.Add(new tVehicleLog {DealNumber = vehicle.FIMAST }));
Int32 stat;
int? status;
if (Int32.TryParse(vehicle.Status, out stat))
status = stat;
else
status = null;
DateTime titled, bounced, dateReceived;
bool trueTitled = DateTime.TryParse(vehicle.Titled, out titled);
bool trueBounced = DateTime.TryParse(vehicle.Bounced, out bounced);
bool trueReceived = DateTime.TryParse(vehicle.DateReceived, out dateReceived);
int dealid = newData.tVehicleDeals.Where(v => v.DealNumber == vehicle.FIMAST).FirstOrDefault().DealID;
tVehicleLog deal = new tVehicleLog
{
DealNumber = vehicle.FIMAST,
StockNumber = vehicle.StockNumber,
BankID = bank.BankID,
CustomerID = cust.CustomerID,
FIManagerID = manag.FIManagerID,
SalesPersonID = sales.SalesPersonID,
VINNumber = null,
DealDate = vehicle.DealDate,
NewUsed = vehicle.NewUsed,
GrossProfit = vehicle.GrossProfit,
AmtFinanced = vehicle.AmtFinanced,
CloseDate = null,
Category = vehicle.RetailLease,
Status = status,
DealershipID = dealership.DealershipID,
NewDeal = false,
Archived = false,
InternalLocationID = location.InternalLocationID,
ChangedBy = vehicle.ChangedBy,
DateChanged = DateTime.Parse(vehicle.DateChanged),
Titled = null,
Bounced = null,
MakeID = make.MakeID,
ModelID = model.ModelID,
DealID = dealid,
CommentID = null
};
if (trueTitled)
deal.Titled = titled;
if (trueBounced)
deal.Bounced = bounced;
if (trueReceived)
deal.DateReceived = dateReceived;
DateTime targetDate = new DateTime(2014, 06, 27);
//if(!newData.tVehicleLogs.Any(v => v.DateChanged >= targetDate))
if(deal.DateChanged >= targetDate && !newData.tVehicleLogs.Any(v => v.DateChanged >= targetDate))
{
newData.tVehicleLogs.Add(deal);
comment = new tVehicleComment
{
Comment = vehicle.Reason,
DealID = deal.DealID,
CurrentComment = false
};
newData.tVehicleComments.Add(comment);
newData.SaveChanges();
int cId = comment.CommentID;
deal.CommentID = cId;
}
}
}
答案 0 :(得分：2)
我认为您不需要在这里使用linq（假设您已将对象拉下来）。只需查看日期。
// pull down the object
var deal = newData.tVehicleLogs.Where(v => v.Id == SOMEID).FirstOrDefault();
DateTime targetDate = new DateTime(2014,06,27);
if (tVehicleLogs.DateChaned <= DateTime.Now
&& tVehicleLogs.DateChaned >= targetDate) {
}
或者，下拉所有符合日期条件的对象并预先覆盖它们。
List<YourObject> list = newData.tVehicleLogs.Where(v => v.DateChanged <= DateTime.Now
&& v.DateChanged >= targetDate).ToList();
foreach(var l in list) {
// do your stuff here
}