时在代码中设置空ID的抱怨让我们假设下面的代码操作的一个DataContext实体框架:当实体ID的SaveChanges
void Context_SavingChanges(object sender, EventArgs e)
{
IEnumerable<ObjectStateEntry> objectStateEntries =
from ose in this.ObjectStateManager.GetObjectStateEntries(EntityState.Added | EntityState.Modified | EntityState.Deleted)
where ose.Entity != null
select ose;
foreach (ObjectStateEntry entry in objectStateEntries)
{
foreach (var field in entry.CurrentValues.DataRecordInfo.FieldMetadata)
{
var guid = Guid.NewGuid();
AuditEntry audit = AuditEntry.CreateAuditEntry(
id: guid,
entitySet: entry.EntitySet.Name,
typeName: entry.Entity.GetType().Name,
entityId: (entry.CurrentValues["Id"] as string) ?? ((entry.State == EntityState.Added) ? "New" : null),
oldValue: (entry.State != EntityState.Added) ? entry.OriginalValues[field.FieldType.Name].ToString() : "New",
newValue: (entry.State != EntityState.Deleted) ? entry.CurrentValues[field.FieldType.Name].ToString() : "Deleted",
modifier: Environment.UserDomainName + "\\" + Environment.UserName,
dbAction: Enum.GetName(typeof(EntityState), entry.State),
field: field.FieldType.Name,
dateStamp: DateTime.Now
);
this.AuditEntries.AddObject(audit);
}
}
}
调用SaveChanges事件当我创建一个新的实体,并试图保存它的变化我得到这个错误:
Cannot insert the value NULL into column 'Id', table 'TimeEF.dbo.AuditEntries'; column does not allow nulls. INSERT fails. The statement has been terminated.
当你可以看到我已经设置了ID,任何想法?错误?
您是否*正面*有问题的记录来自此代码?跟踪SQL。 – 2011-01-19 20:49:29
断点?查看抛出异常的哪一行 - 检查ID。 – RPM1984 2011-01-20 00:07:16