sql-server - VB.NET 似乎无法在两个 EF 代码第一表之间链接数据

Question

我正在尝试首先使用 EF 代码创建一个 Bookings/Accounts 数据库，但在链接数据时遇到了问题

一点背景

数据库目前在此上下文中汇集了 6 个表，但目前我只是试图对以下关联进行排序

Public Class CompanyContext
    Inherits DbContext
    Public Property Drivers As DbSet(Of Driver)
    Public Property Addresses As DbSet(Of Address)
    Public Property Contacts As DbSet(Of ContactDetail)
    Public Property Bookings As DbSet(Of Booking)
    Public Property Accounts As DbSet(Of Account)
    Public Property Vehicles As DbSet(Of Vehicle)
End Class

后面会有更多的数据链接，但我最初的问题如下。我可以创建一个具有以下属性的帐户..

Public Class Account
    Public Property Id As Integer
    Public Property Shortcut As String = ""
    Public Property PaymentMethod As PaymentType
    Public Property CardNumber As Integer
    Public Property CardExpiry As New Date(2000, 1, 1)
    Public Property CardSecurity As Integer
    Public Property AccountAddress As Address
    Public Property Contact As ContactDetail
    Public Property Active As Boolean = True
End Class

Public Class ContactDetail
    Public Property Id As Integer
    Public Property Telephone1 As String = ""
    Public Property Telephone2 As String = ""
    Public Property Email1 As String = ""
    Public Property Email2 As String = ""
    Public Property Fax As String = ""

End Class

Public Class Address
    Public Property AddressId As Integer
    Public Property Company As String = ""
    Public Property FlatBuilding As String = ""
    Public Property Road As String = ""
    Public Property Town As String = ""
    Public Property County As String = ""
    Public Property Country As String = ""
    Public Property PostCode As String = ""
End Class

TextBoxes我使用来自等的数据创建每个帐户ComboBoxes。在保存数据时，所有内容都保存在相应的表中。该表为和表Accounts中的适当行存储了一个 Id，并且来自 的和数据正确存储在那里。AddressesContactsAddressContactAccount

问题

在检索特定的数据时Account，不会返回ContactorAddress数据。我得到的只是具有默认值的属性。我尝试按照 MS 网站上的教程进行操作，但我总是会收到错误，具体取决于我尝试创建导航的方式。恐怕我不完全了解需要什么。这些教程都是用 C# 编写的，但我确定我明白了。

最终，我希望地址和联系数据成为一种可以从其他表链接到的公共池。但是，一旦我发现我现在哪里出错了，这可能会成为另一个问题。这些是我用来保存和检索数据的方法。

selectedAccount是Account类的一个实例

Private Sub AccountSave()
        Using db As New CompanyContext
            If newAccount = True Then
                selectedAccount = New Account
            End If
            With selectedAccount
                .AccountAddress.Company = TxtAccountCompany.Text
                .Shortcut = TxtAccountShortcut.Text
                Select Case CboAccountPaymentMethod.SelectedItem.ToString
                    Case "Account"
                        .PaymentMethod = PaymentType.Account
                    Case "Cash"
                        .PaymentMethod = PaymentType.CashTopay
                    Case "Card"
                        .PaymentMethod = PaymentType.CCToPay
                End Select
                .CardNumber = Integer.Parse(TxtAccountCardNumber.Text)
                .CardExpiry = Date.Parse(MtbAccountCardExpiry.Text)
                .CardSecurity = Integer.Parse(TxtAccountCardSecurity.Text)
                .AccountAddress.FlatBuilding = TxtAccountFlatBuilding.Text
                .AccountAddress.Road = TxtAccountRoad.Text
                .AccountAddress.Town = TxtAccountTown.Text
                .AccountAddress.County = TxtAccountCounty.Text
                .AccountAddress.PostCode = TxtAccountPostcode.Text
                .AccountAddress.Country = TxtAddressCountry.Text
                .Contact.Telephone1 = TxtAccountTelephone1.Text
                .Contact.Telephone2 = TxtAccountTelephone2.Text
                .Contact.Email1 = TxtAccountEmail1.Text
                .Contact.Email2 = TxtAccountEmail2.Text
            End With
            If selectedAccount.Id = 0 Then
                db.Accounts.Add(selectedAccount)
            End If
            db.SaveChanges()
        End Using
        AccountClearInfo()
        AccountDisableEditing()
        AccountRefreshList()
    End Sub

   Private Sub AccountDisplayInfo()
        If selectedAccount IsNot Nothing Then
            TxtAccountCompany.Text = selectedAccount.AccountAddress.Company
            TxtAccountShortcut.Text = selectedAccount.Shortcut
            TxtAccountOustandingBalance.Text = selectedAccount.OustandingBalance.ToString
            Select Case selectedAccount.PaymentMethod
                Case PaymentType.Account
                    CboAccountPaymentMethod.SelectedText = "Account"
                Case PaymentType.CCToPay
                    CboAccountPaymentMethod.SelectedText = "Card"
                Case PaymentType.CashTopay
                    CboAccountPaymentMethod.SelectedText = "Cash"
            End Select
            TxtAccountCardNumber.Text = selectedAccount.CardNumber.ToString
            MtbAccountCardExpiry.Text = selectedAccount.CardExpiry.ToShortDateString
            TxtAccountCardSecurity.Text = selectedAccount.CardSecurity.ToString
            TxtAccountFlatBuilding.Text = selectedAccount.AccountAddress.FlatBuilding.ToString
            TxtAccountRoad.Text = selectedAccount.AccountAddress.Road.ToString
            TxtAccountTown.Text = selectedAccount.AccountAddress.Town.ToString
            TxtAccountCounty.Text = selectedAccount.AccountAddress.County.ToString
            TxtAccountPostcode.Text = selectedAccount.AccountAddress.PostCode.ToString
            TxtAccountCountry.Text = selectedAccount.AccountAddress.Country.ToString
            TxtAccountTelephone1.Text = selectedAccount.Contact.Telephone1
            TxtAccountTelephone2.Text = selectedAccount.Contact.Telephone2
            TxtAccountEmail1.Text = selectedAccount.Contact.Email1
            TxtAccountEmail2.Text = selectedAccount.Contact.Email2
        End If
    End Sub

---

如果这里有用的话，是在幕后生成的用于创建每个表的代码

CREATE TABLE [dbo].[Accounts] (
    [Id]                       INT            IDENTITY (1, 1) NOT NULL,
    [Shortcut]                 NVARCHAR (MAX) NULL,
    [PaymentMethod]            INT            NOT NULL,
    [CardNumber]               INT            NOT NULL,
    [CardExpiry]               DATETIME       NOT NULL,
    [CardSecurity]             INT            NOT NULL,
    [Active]                   BIT            NOT NULL,
    [AccountAddress_AddressId] INT            NULL,
    [Contact_Id]               INT            NULL,
    CONSTRAINT [PK_dbo.Accounts] PRIMARY KEY CLUSTERED ([Id] ASC),
    CONSTRAINT [FK_dbo.Accounts_dbo.Addresses_AccountAddress_AddressId] FOREIGN KEY ([AccountAddress_AddressId]) REFERENCES [dbo].[Addresses] ([AddressId]),
    CONSTRAINT [FK_dbo.Accounts_dbo.ContactDetails_Contact_Id] FOREIGN KEY ([Contact_Id]) REFERENCES [dbo].[ContactDetails] ([Id])
);


GO
CREATE NONCLUSTERED INDEX [IX_AccountAddress_AddressId]
    ON [dbo].[Accounts]([AccountAddress_AddressId] ASC);


GO
CREATE NONCLUSTERED INDEX [IX_Contact_Id]
    ON [dbo].[Accounts]([Contact_Id] ASC);

CREATE TABLE [dbo].[Addresses] (
    [AddressId]    INT            IDENTITY (1, 1) NOT NULL,
    [Company]      NVARCHAR (MAX) NULL,
    [FlatBuilding] NVARCHAR (MAX) NULL,
    [Road]         NVARCHAR (MAX) NULL,
    [Town]         NVARCHAR (MAX) NULL,
    [County]       NVARCHAR (MAX) NULL,
    [Country]      NVARCHAR (MAX) NULL,
    [PostCode]     NVARCHAR (MAX) NULL,
    [Booking_Id]   INT            NULL,
    [Booking_Id1]  INT            NULL,
    CONSTRAINT [PK_dbo.Addresses] PRIMARY KEY CLUSTERED ([AddressId] ASC),
    CONSTRAINT [FK_dbo.Addresses_dbo.Bookings_Booking_Id] FOREIGN KEY ([Booking_Id]) REFERENCES [dbo].[Bookings] ([Id]),
    CONSTRAINT [FK_dbo.Addresses_dbo.Bookings_Booking_Id1] FOREIGN KEY ([Booking_Id1]) REFERENCES [dbo].[Bookings] ([Id])
);


GO
CREATE NONCLUSTERED INDEX [IX_Booking_Id]
    ON [dbo].[Addresses]([Booking_Id] ASC);


GO
CREATE NONCLUSTERED INDEX [IX_Booking_Id1]
    ON [dbo].[Addresses]([Booking_Id1] ASC);

CREATE TABLE [dbo].[ContactDetails] (
    [Id]         INT            IDENTITY (1, 1) NOT NULL,
    [Telephone1] NVARCHAR (MAX) NULL,
    [Telephone2] NVARCHAR (MAX) NULL,
    [Email1]     NVARCHAR (MAX) NULL,
    [Email2]     NVARCHAR (MAX) NULL,
    [Fax]        NVARCHAR (MAX) NULL,
    CONSTRAINT [PK_dbo.ContactDetails] PRIMARY KEY CLUSTERED ([Id] ASC)
);

希望有人能告诉我我的方式的错误。

标签： sql-servervb.netef-code-first