（流畅）Nhibernate 延迟加载及其对 Parallel.ForEach 的影响
当我（从数据库）请求实例时，我通过 FNH 配置了多个实体，以使用 FetchMode.Eager 语法预先加载子实体。现在我的印象是，这会忽略映射中的任何延迟加载，并用“真实”数据填充子实体。
我想要这样做的原因是因为我想使用 Parallel.ForEach 来迭代实体集合并生成一组结果，但我收到以下错误：
[18000] System.InvalidOperationException:
There is already an open DataReader associated with this Command
which must be closed first.
如果我使用 ' NHibernateUtil.Initialize' 初始化所有子实体，然后它按预期工作。
我对使用FetchMode.Eager的理解是否错误？
I have several entities configured via FNH to eager load child entities using the FetchMode.Eager syntax when I request instances (from the database). Now I was under the impression this would ignore any lazy loading in the mapping and populate the child entities with the 'real' data.
The reason why I want to do this is because I want to use a Parallel.ForEach to iterate over a collection of entities and generate a set of results, but I get the following error:
[18000] System.InvalidOperationException:
There is already an open DataReader associated with this Command
which must be closed first.
If I use ' NHibernateUtil.Initialize' to initialise all child entities then it works as expected.
Am I wrong in my understanding in the use of FetchMode.Eager?
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我真的永远不会尝试这样做。每个 Parallel.ForEach 函数都可以在不同的线程上运行。根据您的配置，NHibernate ISession 存储在一个线程中，这意味着除了调用线程之外的任何其他线程都无法访问该会话，这就是整个事情失败的原因。
就我个人而言，我会将整个内容检索到传输对象中，然后对其执行 Parallel.ForEach 。
I really would not ever try and do that. Each Parallel.ForEach func can run on a different thread. Depending on your configuration, the NHibernate ISession is stored against a thread meaning anything other than the calling thread cannot access the session which is why the whole thing fails.
Personally I'd retrieve the whole thing into a transfer object then do the Parallel.ForEach on that.