2

我有以下代码

 Imports System.Data


 Public Class ReservationList

Private Sub GuestListToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles GuestListToolStripMenuItem.Click
    'Show the registration table

    GuestListForm.Show()
    Me.Hide()
End Sub

Private Sub HighriseToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles HighriseToolStripMenuItem.Click
    ' Shows the About Box
    highriseAboutBox.Show()
End Sub

Private Sub ExitToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitToolStripMenuItem.Click
    ' Terminates program
    highriseAboutBox.Show()
    Me.Close()
End Sub

Private Sub NewReservationToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles NewReservationToolStripMenuItem.Click
    ' Restarts the program
    NewReservationForm.Show()
    Me.Close()
End Sub

Private Sub ExitButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitButton.Click
    ' terminates program

    highriseAboutBox.Show()
    Me.Close()
End Sub

Private Sub ReservationList_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

    'TODO: This line of code loads data into the 'CottagesDataSet.Guests' table. You can move, or remove it, as needed.
    Me.GuestsTableAdapter.Fill(Me.CottagesDataSet.Guests)
    'TODO: This line of code loads data into the 'CottagesDataSet.Reservations' table. You can move, or remove it, as needed.
    Me.ReservationsTableAdapter.Fill(Me.CottagesDataSet.Reservations)

End Sub

Private Sub Last_NameLabel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)

End Sub


Private Sub Last_NameComboBox_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Last_NameComboBox.SelectedIndexChanged

End Sub
End Class

当我运行（调试）程序时，我得到了这个

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我正在尝试设置父子关系以显示如下所示：

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这就是我的 .xsd 关系

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所以这就是我可以向你展示的全部内容。知道为什么我会收到此错误吗？一切似乎都在检查我以相同方式设置的另一个数据库。我也跟着一本书教程，并没有错过任何东西。我几乎要放弃整个想法，但我想让它发挥作用。

谢谢

4

1 回答 1

1

当您遇到某种形式的数据库架构错误时，会出现“无法启用约束”错误。

要修复它们：

  1. 确保您的主键不允许空值，并且您尚未在其中存储任何空值。

  2. 确保您的“关系”列（姓氏、来宾）不为空，并且您尚未在其中存储任何空值。

  3. 如果您更改了 Last Name, Guest 可以存储的字符串的长度，在添加数据后，您可能会遇到这里遇到的问题：http: //social.msdn.microsoft.com/Forums/en-US/Vsexpressvb/thread/ 27aec612-5ca4-41ba-80d6-0204893fdcd1/

于 2013-05-06T00:49:36.540 回答