ADO.NET Entity Framework 分层参考
part 2: Optimistic Concurrency Updates using Entity Framework in N-Tier and N-Layer Applications (Part 2)
http://news.cnblogs.com/n/43866/
part 2: Optimistic Concurrency Updates using Entity Framework in N-Tier and N-Layer Applications (Part 2)
http://news.cnblogs.com/n/43866/