不同的EF 4 SaveOptions对ObjectContext有什么影响？ [英] What effect do the different EF 4 SaveOptions have on the ObjectContext?

问题描述

我正在尝试解决与这里概述的错误非常相似的错误：

在.NET Entity框架中调用SaveChanges时，InvalidOperationException

看来，解决方案（我还没有尝试，不可否认）是将System.Data.Objects.SaveOptions.None作为SaveChanges（）方法的SaveOptions参数传递。

所以在我这样做之前，我正在试图明白不同的SaveOptions是如何工作的（None，AcceptAllChangesAfterSave，DetectAllChanges）。我还没有找到一个清楚的解释，但我也不知道默认是什么。有人可以澄清吗

谢谢！

更新：我在此发布了实际的问题问题：在尝试使用EF 4迭代添加对象时， System.InvalidOperationException

解决方案

好问题（+1）。

简而言之（从我的理解）：

SaveOptions.DetectChangesBeforeSave ：这是默认值。当您 ObjectContext.SaveChanges（）时，方法 DetectChanges（）被调用以在同步的附件实体中OSM。

SaveOptions.AcceptAllChangesAfterSave ：当您执行 ObjectContext.SaveChanges（），方法 AcceptAllChanges（）被调用 - 这是OSM的内容，图中的实体被迭代，地址和设置为不变/分离。

SaveOptions.None ：当您执行 ObjectContext.SaveChanges（），更改ar e绝对保存 - 根本没有同步。图表中的任何东西都将被保存。

根据我的经验，我并没有搞砸这个 - 我把它留作默认（DetectChangesBeforeSave）。 p>

有时候用POCO我听说你需要明确地调用 DetectChanges ，但是我从来没有看过推荐/解决方案将SaveOptions更改为none。

您确定该问题的解决方案是将SaveOptions设置为none？也许你应该提供细节（或问一个单独的问题）你的错误，因为这样的改变会影响你的整个持久层。

I'm trying to resolve an error very similar to the one outlined here:

InvalidOperationException when calling SaveChanges in .NET Entity framework

It appears that the solution (which I have not tried yet, admittedly) is to pass System.Data.Objects.SaveOptions.None as the SaveOptions parameter for the SaveChanges() method.

So before I do that, I'm trying to understand exactly how the different SaveOptions work (None, AcceptAllChangesAfterSave, DetectAllChanges). I haven't been able to find a clear explanation of it however, nor am I sure what the default is. Can anyone clarify?

Thanks!

UPDATE: I have posted the actual problem question here: System.InvalidOperationException when trying to iteratively add objects using EF 4

解决方案

Good question (+1).

In a nutshell (from what i understand):

SaveOptions.DetectChangesBeforeSave : this is the default. When you do ObjectContext.SaveChanges(), the method DetectChanges() is called to synchronized attach entities in the OSM.

SaveOptions.AcceptAllChangesAfterSave : When you do ObjectContext.SaveChanges(), the method AcceptAllChanges() is called - which is the guts of the OSM, where the entities in the graph are iterated, addresses and set to Unchanged/Detached.

SaveOptions.None : When you do ObjectContext.SaveChanges(), changes are saved immeditately - no synchronization at all. Whatever is in the graph is what will be saved.

In my experience i have not messed with this - i've left it as the default (DetectChangesBeforeSave).

Sometimes with POCO's i have heard you need to explicitly call DetectChanges, but i've never seen a recommendation/solution to change the SaveOptions to none.

Are you sure the solution in that question is to set SaveOptions to none? Maybe you should provide detail (or ask a seperate question) as to the error your getting, as a change like this will affect your entire persistence layer.

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