我有一个实体,我检索如下,并与上下文分离:
ctx.Reviews.MergeOption = MergeOption.NoTracking;
Review review = (from r in ctx.Reviews.Include("ReviewNotes")
where r.ReviewID == reviewID
select r).First();
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然后我对关系中的对象进行了更改:
if (review.ReviewNotes.Count > 0)
{
ReviewNote r = review.ReviewNotes.ElementAt(0);
r.Note = "Ugg " + DateTimeOffset.Now.ToString();
r.CreatedDate = DateTimeOffset.Now;
}
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然后我附加了Object并循环子节点并在需要时更改它的实体状态.保存更改完成后,不会更新任何内容:
ctx.Reviews.Attach(review);
foreach (ReviewNote item in review.ReviewNotes)
{
if (item.ReviewNoteID == 0)
{
ctx.ObjectStateManager.ChangeObjectState(item, EntityState.Added);
}
else
{
key = ctx.CreateEntityKey("ReviewNotes", item);
if (ctx.TryGetObjectByKey(key, out original))
{
ctx.ApplyCurrentValues<ReviewNote>(key.EntitySetName, item);
}
}
}
ctx.ObjectStateManager.ChangeObjectState(review, EntityState.Modified);
ctx.SaveChanges();
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