We're getting an inconsistent null reference exception while assigning a non-nullable scalar variable to an Entity Framework domain object property. I understand what a null reference exception is, but I can't understand how you would get one when assigning a non-null value to a property of a non-null EF domain object.
The domain object looks like this:
[DataContract]
[Table("Participant", Schema = "tour")]
public partial class Participant
{
public Participant()
{
}
[DataMember]
[Key]
public int ParticipantID { get; set; }
...
public DateTime? AutopayLastAttemptedUtc { get; set; }
}
The area where we are getting the exception is:
DateTime utcNow = DateTime.UtcNow;
// The below line throws the Null Reference Exception.
participant.AutopayLastAttemptedUtc = utcNow;
ParticipantService.Update(participant);
I still get an exception on the same line if I add some debug code to prove variables are not null:
DateTime utcNow = DateTime.UtcNow;
// This line proves that participant is not null and that
// AutopayLastUpdatedUtc can be read (not that that really
// matters because we only want to set it
TelemetryClient.TrackTrace("Participant", SeverityLevel.Information, new Dictionary<string, string> {
{ "ParticipantId", participant.ParticipantID.ToString() },
{ "AutopayLastUpdatedUtc", participant.AutopayLastAttemptedUtc.ToString() }
});
// The below line throws the Null Reference Exception.
participant.AutopayLastAttemptedUtc = utcNow;
ParticipantService.Update(participant);
I don't understand what could possibly be null
- participant can't be null because we use it in the debug code on the line above
- utcNow can't be null because it's a non-nullable type
- AutopayLastUpdatedUtc is a standard EF setter
Note that I am not asking what a null reference exception is. I am asking how a null reference exception could possibly happen when assigning a non-null value to a property of a non-null object.
