Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
345 views
in Technique[技术] by (71.8m points)

c# - Entity Framework SaveChanges() not updating the database

var paymentAttempt = _auctionContext.PaymentAttempts.Where(o => o.Id == paymentAttemptId).SingleOrDefault();
if (paymentAttempt != null)
{
    paymentAttempt.PaymentAttemptStatusId = (int)PaymentAttemptStatus.Defunct;
    paymentAttempt.PaymentAttemptStatus = _auctionContext.PaymentAttemptStatuses.Where(pas => pas.Id == paymentAttempt.PaymentAttemptStatusId).First();

    var relevantWinningBidsTotalPrices = _auctionContext.GetWinningBidsTotalPricesForPaymentAttempt(paymentAttemptId).ToArray();

    foreach (var winningBid in relevantWinningBidsTotalPrices)
    {
        winningBid.Locked = false;
        _auctionContext.UpdateObject(winningBid);
    }
    _auctionContext.SaveChanges();
}

In the above code after

_auctionContext.SaveChanges();

is called winningBid is updated as expected but paymentAttempt isn't. Why is this? It is really frustrating. There is no error either. I would expect a failure to occur if there was a problem like EF wasn't tracking the object or something like that, but no such error is happening.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

That's because you need to pass the paymentAttempt object to your context, to let it know that it is an object that needs to be updated.

For example, assuming that _auctionContext is an instance of DbContext:

// any changes related to the paymentAttempt object 

_auctionContext.Entry(paymentAttempt).State = EntityState.Modified;

foreach (var winningBid in relevantWinningBidsTotalPrices)
{
   winningBid.Locked = false;
   _auctionContext.UpdateObject(winningBid);
}

_auctionContext.SaveChanges();

Another option is the Attach method:

_auctionContext.Attach(paymentAttempt);
_auctionContext.ObjectStateManager.ChangeObjectState(paymentAttempt, System.Data.EntityState.Modified);

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...