EF状态跟踪测试

最新推荐文章于 2025-05-30 08:55:42 发布

weixin_30483013

最新推荐文章于 2025-05-30 08:55:42 发布

阅读量149

点赞数

CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/FoundationSoft/archive/2011/06/22/2086682.html

本文通过具体测试案例，验证了Entity Framework中实体的状态变化，包括Detach后的EntityKey存在性、ObjectContext被Dispose后实体状态的变化及不同MergeOption设置下实体属性变更的跟踪情况。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

[TestClass]
public class EFTest
{
//测试EntityKey, EntityState, ObjectContext
//1. Detach后EntityKey是否存在？是
//2. EntityKey占多大内存？小
//3. Entity所依附的ObjectContext被Dispose后，EntityState是否自动变为Detached? 否
//4. 当MergeOption为NoTracking时，Entity中属性的改变是否会被跟踪？不会，为Detached状态
//4. Entity所依附的ObjectContext被Dispose后，Entity中属性的改变是否会被跟踪？
[TestMethod]
public void trackTest()
{
int id = 5;
FinanceContext context = new FinanceContext();
//DataContext在默认情况下的行为
BusinessApplication entity = context.BusinessApplication.Where(b => b.Id == id).Single();
Assert.AreEqual(EntityState.Unchanged, entity.EntityState);
entity.Title = "改变一下";
Assert.AreEqual(EntityState.Modified, entity.EntityState);
context.Detach(entity);
Assert.IsNotNull(entity.EntityKey);
//在DataContext Dispose以后的行为
entity = context.BusinessApplication.Where(b => b.Id == id).Single();
context.Dispose();
Assert.AreEqual(EntityState.Unchanged, entity.EntityState);
entity.Title = "改变一下";
Assert.AreEqual(EntityState.Modified, entity.EntityState);

//DataContext当MergeOption.NoTracking时的行为
context = new FinanceContext();
entity = null;
context.BusinessApplication.MergeOption = MergeOption.NoTracking;
entity = context.BusinessApplication.Where(b => b.Id == id).Single();
Assert.AreEqual(EntityState.Detached, entity.EntityState);
entity.Title = "改变一下";
Assert.AreEqual(EntityState.Detached, entity.EntityState);
context.Dispose();

//DataContext当MergeOption.OverwriteChanges时的行为
context = new FinanceContext();
entity = null;
context.BusinessApplication.MergeOption = MergeOption.OverwriteChanges;
entity = context.BusinessApplication.Where(b => b.Id == id).Single();
Assert.AreEqual(EntityState.Unchanged, entity.EntityState);
entity.Title = "改变一下";
Assert.AreEqual(EntityState.Modified, entity.EntityState);
context.Dispose();

}
}

转载于:https://www.cnblogs.com/FoundationSoft/archive/2011/06/22/2086682.html