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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.

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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);

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