我怎么错了我的DataContext? [英] How did I wrong my DataContext?

问题描述

我已经使用LINQ To SQL已有一段时间了，而我通常在解决方案中的工作如下:

I've been working with LINQ To SQL for some time now, and what I usually do in a solution is the following:

• 在一个项目中，我创建一个dbml模式.
• 在另一个项目中，我创建一个简单的DataAccessLayer(DAL)，它知道我的第一个项目，并实例化一个DataContext.
• 在第三个项目(业务逻辑)中，我实例化DAL.

这通常效果很好.但是，这一次，我不知道为什么，但是"It"不起作用. 它"是我正在更新数据库".我更改了代码以进行一些测试，但结果却是我不明白.

This usually works well. However, this time, I don't know why, but "It" doesn't work. "It" being "Me updating the database". I changed my code around to do some tests, and I get a result I don't understand.

MyDataContext dataContext = new MyDataContext(MyConnectionString);
DataBaseItem dbi = (from item in dataContext.DataBaseItems
    where item.ID == 1
    select item).First();
dbi.Name= "toto";
// dataContext.GetChangeSet() tells me nothing changed.

我更深入地研究了bdi.Name = "toto";，并将其与工作所在的项目(都是设计人员生成的代码)中类似的值赋值进行了比较，发现缺少一些代码(我在此处写下了这些代码，但我评论了他们，以便您看到缺少的内容):

I dug deeper by breaking into the bdi.Name = "toto"; and compared it with a similar value assignment in a project where it works (both are designer generated code) and saw that some code was missing (I wrote them down there, but I commented them so you see what is missing) :

[Column(Storage="_Name", DbType="NVarChar(250)")]
public string Name
{
    get
    {
        return this._Name;
    }
    set
    {
        if ((this._Name!= value))
        {
            //this.OnLayoutChanging(value);
            //this.SendPropertyChanging();
            this._Name= value;
            //this.SendPropertyChanged("Name");
            //this.OnLayoutChanged();
        }
    }
}

任何人都可以告诉我这些行为何丢失，我在哪里弄糟了?

Anyone can tell me how come these lines are missing, and where did I messed up?

当我执行dataContext.Refresh(RefreshMode.KeepChanges, dataContext.DataBaseItems);时，出现错误:

When I do dataContext.Refresh(RefreshMode.KeepChanges, dataContext.DataBaseItems);, I get an error:

无法识别指定用于刷新的对象.

An object specified for refresh is not recognized.

推荐答案

该错误是在IDE(VS2008)中. IDE生成或重新生成的任何Linq-to-Sql对象都是错误的.要解决此问题，我必须:

The error was within the IDE (VS2008). The generation, or regeneration, of any Linq-to-Sql object by the IDE was faulty. To fix the problem, I had to :

1. 删除错误的对象.
2. 关闭Visual Studio.
3. 重新打开Visual Studio.
4. 重新创建对象.

不做第一站，而是通过更改参数来重新生成对象是可行的，但是由于我不知道如何重现该问题，所以我无法对其进行测试.

Not doing the first stop and instead have the object regenerated by changing a parameter could have worked, but I can't test it, since I don't know how to reproduce the problem.

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