sql - 数据库会读但不会写

Question

我遇到一个问题，我无法对 Sql server .mdf 数据库进行预订，但我可以读取它。

没有出现错误消息，我已经尝试了所有我能想到的方法。任何帮助将不胜感激，并提前致谢! 这是用于插入命令的代码:

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

    Dim SQLCode As New SQLCode
    Dim con As New SqlConnection
    Dim cmd As New SqlCommand
    Dim lrd As SqlDataReader
    Dim inscmd As New SqlCommand

    cmd.Parameters.AddWithValue("@StaffInitials", lblStaffInitials.Text.Trim())
    lblStaffInitials.Text = lblStaffInitials.Text
    cmd.Parameters.AddWithValue("@Week", lblWeek.Text.Trim)
    lblWeek.Text = lblWeek.Text
    cmd.Parameters.AddWithValue("@Period", (lblPeriod.Text.Trim))
    lblPeriod.Text = lblPeriod.Text
    cmd.Parameters.AddWithValue("@Day", lblDay.Text.Trim)
    lblDay.Text = lblDay.Text
    cmd.Parameters.AddWithValue("@Subject", lblSubject.Text.Trim)
    lblSubject.Text = lblSubject.Text
    cmd.Parameters.AddWithValue("@YearGroup", lblYear.Text.Trim)
    lblYear.Text = lblYear.Text
    cmd.Parameters.AddWithValue("@NumberOfPupils", (lblNoOfPupils.Text.Trim))
    lblNoOfPupils.Text = lblNoOfPupils.Text
    cmd.Parameters.AddWithValue("@ControlledAssesment", lblControlledAssesment.Text.Trim)
    lblControlledAssesment.Text = lblControlledAssesment.Text
    cmd.Parameters.AddWithValue("@Room", lblRoom.Text.Trim)
    lblRoom.Text = lblRoom.Text
    cmd.Parameters.AddWithValue("@Session", txtSession.Text.Trim)
    txtSession.Text = txtSession.Text

con.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings("RoomBookingSystem.My.MySettings.Database1ConnectionString1").ConnectionString
    Try
        Using cn As New SqlConnection(con.ConnectionString)
            con.Open()
            inscmd.CommandText = "INSERT INTO Booking (Week, Day, Period, Subject, YearGroup, StaffInitials,NumberOfPupils,Session,Room,ControlledAssesment) VALUES (@Week,@Day,@Period,@Subject,@YearGroup,@StaffInitials, @NumberOfPupils,@Session,@Room,@ControlledAssesment)"
            inscmd.Connection = con
            inscmd.ExecuteNonQuery()
            inscmd.Parameters.Clear()
        End Using

    Finally
        con.Close()
    End Try
    MsgBox("Your Booking Has Been Made Successfully")
    Clicky = False
    MainViewForm.btnBackToBooking.Visible = False
    FormView.Show()
    Me.Hide()
End Sub

Answer 1

据我所知，问题出在数据库位置。

当程序被调试时，一个数据库的副本被放置在 bin/debug 文件夹中，如果你在这里查看，你会看到副本，你的代码将有权访问这个数据库和不是原始数据库 (如果您单击“显示所有文件”然后转到 bin/调试文件，然后使用数据库资源管理器打开，您可以看到上次调试/运行时估算的数据)

要解决此问题，您需要执行以下操作:

你的连接字符串

 con.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings("RoomBookingSystem.My.MySettings.Database1ConnectionString1").ConnectionString

将连接到前面提到的 bin 文件夹中的数据库。

您需要进入您的 app.config 文件，找到您数据库的特定位置，并将其用于您的连接字符串，这将允许您从非副本的数据库。