如何在C#中插入依赖LINQ到SQL实体而不进行手动ID更新？

我有两个模型

型号Foo

[System.Data.Linq.Mapping.Table(Name = ...)]
public class Foo
{
  [System.Data.Linq.Mapping.Column(IsPrimaryKey = true, IsDbGenerated = true)]
  public int ID { get; set; }

  [System.Data.Linq.Mapping.Column(IsPrimaryKey = true)]
  public int BarID { get; set; }
  
  // 1:1 association - foo <> bar
  [System.Data.Linq.Mapping.Association(Name = "FK_Foo_Bar", Storage = "mBar", OtherKey = "ID", ThisKey = "BarID")]
  public Bar CurrentRevision
  {
    get { return mBar.Entity; }
    set { mBar.Entity = value; }
  }
  
  private System.Data.Linq.EntityRef<Bar> mBar = new System.Data.Linq.EntityRef<Bar>();
}

[System.Data.Linq.Mapping.Table(Name = ...)]
public class Foo
{
  [System.Data.Linq.Mapping.Column(IsPrimaryKey = true, IsDbGenerated = true)]
  public int ID { get; set; }

  [System.Data.Linq.Mapping.Column]
  public int BarID { get; set; }

  // 1:1 association - foo <> bar
  [System.Data.Linq.Mapping.Association(Name = "FK_Foo_Bar", Storage = "mBar", OtherKey = "ID",
    ThisKey = "BarID", IsForeignKey=true)]
  public Bar CurrentRevision
  {
    get { return mBar.Entity; }
    set { mBar.Entity = value; }
  }

  private System.Data.Linq.EntityRef<Bar> mBar = new System.Data.Linq.EntityRef<Bar>();
}

将

lFoo

行和

lBar

行添加到数据库中，但

FooID

和

BarID

字段保持为零

---

有没有办法让框架使用正确的ID自动更新列

FooID

和

BarID

，而不是手动更新？

以下问题导致了这一点，正如我在MSDN上阅读时发现的：

一个类中有多个

IsPrimaryKey

表示一个复合键，DB没有

缺少

IsForeignKey

属性

在调用

InsertOnSubmits（）

后直接双向链接对象将无法工作，因为这会引发异常

所以正确的方法是

型号Foo

[System.Data.Linq.Mapping.Table(Name = ...)]
public class Foo
{
  [System.Data.Linq.Mapping.Column(IsPrimaryKey = true, IsDbGenerated = true)]
  public int ID { get; set; }

  [System.Data.Linq.Mapping.Column(IsPrimaryKey = true)]
  public int BarID { get; set; }
  
  // 1:1 association - foo <> bar
  [System.Data.Linq.Mapping.Association(Name = "FK_Foo_Bar", Storage = "mBar", OtherKey = "ID", ThisKey = "BarID")]
  public Bar CurrentRevision
  {
    get { return mBar.Entity; }
    set { mBar.Entity = value; }
  }
  
  private System.Data.Linq.EntityRef<Bar> mBar = new System.Data.Linq.EntityRef<Bar>();
}

[System.Data.Linq.Mapping.Table(Name = ...)]
public class Foo
{
  [System.Data.Linq.Mapping.Column(IsPrimaryKey = true, IsDbGenerated = true)]
  public int ID { get; set; }

  [System.Data.Linq.Mapping.Column]
  public int BarID { get; set; }

  // 1:1 association - foo <> bar
  [System.Data.Linq.Mapping.Association(Name = "FK_Foo_Bar", Storage = "mBar", OtherKey = "ID",
    ThisKey = "BarID", IsForeignKey=true)]
  public Bar CurrentRevision
  {
    get { return mBar.Entity; }
    set { mBar.Entity = value; }
  }

  private System.Data.Linq.EntityRef<Bar> mBar = new System.Data.Linq.EntityRef<Bar>();
}

不幸的是，作为一个侧节点，在我的例子中，使用

IsForeignKey

属性值会改变查询行为（例如，LINQ to SQL生成交叉连接而不是内部连接）和整个程序逻辑

[System.Data.Linq.Mapping.Table(Name = ...)]
public class Bar
{
  [System.Data.Linq.Mapping.Column(IsPrimaryKey = true, IsDbGenerated = true)]
  public int ID { get; set; }

  [System.Data.Linq.Mapping.Column]
  public int FooID { get; set; }

  // 1:1 association - bar <> foo
  [System.Data.Linq.Mapping.Association(Name = "FK_Bar_Foo", Storage = "mFoo", OtherKey = "ID",
    ThisKey = "FooID", IsForeignKey=true)]
  public Foo Folder
  {
    get { return mFoo.Entity; }
    set { mFoo.Entity = value; }
  }

  private System.Data.Linq.EntityRef<Foo> mFoo = new System.Data.Linq.EntityRef<Foo>();
}

lFoo = new Foo();
DataContext.Foos.InsertOnSubmit(lFoo);    

lBar = new Bar();
DataContext.Bars.InsertOnSubmit(lBar);    

DataContext.SubmitChanges();    

lBar = lFoo; // link foo to bar
lFoo = lBar; // link bar to foo

DataContext.SubmitChanges();