EF 执行顺序--先删除在更新和添加

public void AcceptAllChanges()
{
if (this.ObjectStateManager.SomeEntryWithConceptualNullExists())
{
throw new InvalidOperationException(System.Data.Entity.Strings.ObjectContext_CommitWithConceptualNull);
}
foreach (ObjectStateEntry entry in this.ObjectStateManager.GetObjectStateEntries(EntityState.Deleted))
{
entry.AcceptChanges();
}
foreach (ObjectStateEntry entry2 in this.ObjectStateManager.GetObjectStateEntries(EntityState.Modified | EntityState.Added))
{
entry2.AcceptChanges();
}
}