使用 linq 时从 WCF 服务返回什么？
使用 LINQ 时，我应该从 WCF 服务返回什么？例如：
var res = from q in context.cust
select q;
LINQ 遵循延迟执行，因此在运行 for 循环之前该语句不会执行任何操作。这意味着我不能只返回 res.那我应该返回什么呢？每次我想从 WCF 服务返回数据时，是否需要编写一个 for 循环并填充对象并返回它的列表？是否没有 ADO.NET DataSet 的等效项，它遵循断开连接的体系结构，并且非常适合在不同层之间以及从 Web 服务或 WCF 服务移动数据？
What should i return from a WCF service when using LINQ? e.g.:
var res = from q in context.cust
select q;
The LINQ follows Deferred Execution and thus the statement doesn't do anything until a for loop is ran. This means i can't just return res. Then what should i return? Do i need to write a for loop and populate objects and return it's List every time i want to return data from WCF service? Is there no equivalent of ADO.NET DataSet which follows disconnected architecture and is ideal for moving data between different tiers and from web service or WCF service?
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执行被推迟到实际请求数据为止，您是对的，这可能是一个 for 循环，但也可能是在需要序列化以通过 WCF 传输时。如果您使 WCF 服务返回 IEnumerable，则将执行查询并返回结果。
Execution is deferred until the data is actually requested, you're right that that may be a for loop but it would also be when it needs to be serialized for transfer via WCF. If you make your WCF service return IEnumerable then the query will be executed and the results returned.
如果将其返回为
IEnumerable，WCF 序列化程序应执行查询。但我通常这样做
If you return it as
IEnumerable<cust>the WCF serializer should execute the query.But I usually do
由于查询中提到的上下文，您必须通过将结果转换为数组或列表来显式执行查询。上下文可能与 Linq-To-Sql 或 EF 相关，并且在序列化期间，延迟执行很有可能失败，因为上下文已经关闭。
Because of context mentioned in your query you have to execute query explicitly by converting result to array or list. Context is probably related to Linq-To-Sql or EF and there is a big chance that during serialization the deffered execution fails because the context will be already closed.