The null value cannot be assigned to a member with type System.Int64 which is a non-nullable value t
- by BritishDeveloper
I'm getting the following error in my MVC2 app using Linq to SQL (I am new to both). I am connected to an actual SQL server not weird mdf:
System.InvalidOperationException The null value cannot be assigned to a member with type System.Int64 which is a non-nullable value type
My SQL table has a column called MessageID. It is BigInt type and has a primary key, NOT NULL and an IDENTITY 1 1, no Default
In my dbml designer it has the following declaration for this field:
[global::System.Data.Linq.Mapping.ColumnAttribute(Storage="_MessageId", AutoSync=AutoSync.OnInsert, DbType="BigInt NOT NULL IDENTITY", IsPrimaryKey=true, IsDbGenerated=true)]
public long MessageId
{
get
{
return this._MessageId;
}
set
{
if ((this._MessageId != value))
{
this.OnMessageIdChanging(value);
this.SendPropertyChanging();
this._MessageId = value;
this.SendPropertyChanged("MessageId");
this.OnMessageIdChanged();
}
}
}
It keeps telling me that null cannot be assigned - I'm not passing through null! It's a long - it can't even be null!
Am I doing something stupid? I can't find a solution anywhere!
I made this work by changing the type of this property to Nullable<long> but surely this can't be right?
Update:
I am using InsertOnSubmit. Simplified code:
public ActionResult Create(Message message)
{
if (ModelState.IsValid)
{
var db = new MessagingDataContext();
db.Messages.InsertOnSubmit(message);
db.SubmitChanges(); //line 93 (where it breaks)
}
}
breaks on SubmitChanges() with the error at the top of this question.
Update2:
Stack trace:
at Read_Object(ObjectMaterializer`1 )
at System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReader`2.MoveNext()
at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source)
at System.Data.Linq.ChangeDirector.StandardChangeDirector.DynamicInsert(TrackedObject item)
at System.Data.Linq.ChangeDirector.StandardChangeDirector.Insert(TrackedObject item)
at System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode)
at System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode)
at Qanda.Controllers.MessagingController.Ask(Message message) in C:\Qanda\Qanda\Controllers\MessagingController.cs:line 93
Update3:
No one knows and I don't have enough clout to offer a bounty! So continued on my ASP.NET blog. Please help!