Question

我想通过使用BLToolkit将一些新记录添加到父/子关系中的一组表中。不幸的是，我无法弄清楚我错过了什么，因为在提交之后，我只在我的数据库中拥有父行。

当我在将父对象添加到parents-List之前检查它时，它包含了像期望的Child-Object。我很确定我在SQLQuery-Bit中遗漏了一些东西，但我不知道是什么。

以下是我设置的内容。

用于创建表的SQL代码

    CREATE TABLE [dbo].[PARENTS](
        [ID] [int] IDENTITY(1,1) NOT NULL,
        [SOME_VALUE] [int] NOT NULL,
        CONSTRAINT [PK_PARENT] PRIMARY KEY CLUSTERED 
        (
            [ID] ASC
        )WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
    ) ON [PRIMARY]

    CREATE TABLE [dbo].[CHILDS](
        [ID] [int] IDENTITY(1,1) NOT NULL,
        [PARENT_ID] [int] NOT NULL,
        [SOME_TEXT] [nvarchar](50) NOT NULL,
        CONSTRAINT [PK_CHILD] PRIMARY KEY CLUSTERED 
        (
            [ID] ASC
        )WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
    ) ON [PRIMARY]

    GO

    ALTER TABLE [dbo].[CHILDS]  WITH CHECK ADD  CONSTRAINT [FK_CHILD_PARENT] FOREIGN KEY([PARENT_ID])
    REFERENCES [dbo].[PARENTS] ([ID])
    GO

    ALTER TABLE [dbo].[CHILDS] CHECK CONSTRAINT [FK_CHILD_PARENT]

班级

[TableName("PARENTS")]
public class Parent
{
    public Parent()
    {
        Children = new List<Child>();
    }

    [MapField("ID"), PrimaryKey, NonUpdatable]
    public int Id;

    [MapField("SOME_VALUE")]
    public int SomeValue;

    [Association(ThisKey = "ID", OtherKey = "PARENT_ID", CanBeNull = false)]
    public List<Child> Children;
}

[TableName("CHILDS")]
public class Child
{
    [MapField("ID"), PrimaryKey, NonUpdatable]
    public int Id;

    [MapField("SOME_TEXT")]
    public string SomeText;

    [Association(ThisKey = "PARENT_ID", OtherKey = "ID", CanBeNull = false)]
    public Parent Parent;
}

插入行的代码

using (DbManager db = new DbManager())
{
    db.BeginTransaction();
    SqlQuery<Parent> query = new SqlQuery<Parent>();

    IList<Parent> parents = new List<Parent>();
    for (int i = 0; i < 10; i++)
    {
        Parent parent = new Parent();
        parent.SomeValue = i;

        Child child = new Child();
        child.SomeText = i.ToString();

        parent.Children.Add(child);
        parents.Add(parent);
    }
    query.Insert(db, 10, parents);
    db.CommitTransaction();
}

Answer 1

您的代码没有任何问题。 BLToolkit是一个轻量级的ORM，这意味着它不会跟踪对象的状态。这与其他ORM不同，如EF，L2SQL，NHibernate。在BLToolkit中，您可以直接使用数据库。你应该做的是：

插入Parent并获取其身份。
然后插入Child并将其设置为父ID。

此外，当您插入/更新或删除时，请在try / catch中执行此操作

using (DbManager db = new DbManager())
{
    try
    {
        db.BeginTransaction();

        // do something here...

        db.CommitTransaction();
    }
    catch
    {
        db.RollbackTransaction();
    }
}

如何使用BLToolkit添加父子关系

1 个答案: