单击保存按钮

Question

我一直有这个问题，我的搜索引起了更多的困惑。目前我拥有的是一个访问数据库，当windows窗体加载时，它会提取一个技术列表并将其放入ComboBox。一旦您选择了您正在寻找的技术，您点击一个按钮就会拉出日期（当他们的保险到期时）。我已经成功地获取它来拉日期并让它填充DateTimePicker的截止日期。

我遇到问题的时候，就是我更改日期并尝试将其保存回数据库。我没有收到任何错误，我甚至得到了我的＃34;记录保存＆＃34;信息。我感到茫然，任何帮助都会有所帮助。

Imports System.Data.OleDb

Public Class GateTechTesting
    Private Sub GateTechTesting_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    Dim MainTechDataFile As String
    Dim MainTechConnString As String
    Dim MainTechConnection As OleDbConnection = New OleDbConnection
    Dim MR As OleDbDataReader

    Dim provider As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source ="
    MainTechDataFile = "C:\Users\Jmcn\Desktop\GateTechDBTest.accdb"
    MainTechConnString = provider & MainTechDataFile
    MainTechConnection.ConnectionString = MainTechConnString


    MainTechConnection.Open()

    Dim query As String = "Select * From Gtech"
    Dim command As OleDbCommand = New OleDbCommand(query, MainTechConnection)
    MR = command.ExecuteReader
    While MR.Read()
        ComboBox1.Items.Add(MR("Gate Tech").ToString)

    End While

    MainTechConnection.Close()
End Sub

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    If ComboBox1.SelectedItem = "" Then
        MessageBox.Show("Nothing Selected")
    Else
        Dim setech As String = ComboBox1.SelectedItem
        Dim MainTechDataFile As String
        Dim MainTechConnString As String
        Dim MainTechConnection As OleDbConnection = New OleDbConnection
        Dim MR As OleDbDataReader

        Dim provider As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source ="
        MainTechDataFile = "C:\Users\Jmcn\Desktop\GateTechDBTest.accdb"
        MainTechConnString = provider & MainTechDataFile
        MainTechConnection.ConnectionString = MainTechConnString


        MainTechConnection.Open()

        Dim query As OleDbCommand = New OleDbCommand("Select * From Gtech WHERE [Gate Tech] = @tech", MainTechConnection)
        query.Parameters.AddWithValue("@tech", setech)


        MR = query.ExecuteReader
        While MR.Read()
            DateTimePicker1.Text = MR("Liability").ToString

        End While

        MainTechConnection.Close()
    End If
End Sub

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

        Dim satech As String = ComboBox1.SelectedItem
        Dim cnnOLEDB As OleDbConnection = New OleDbConnection
        Dim cmdOLEDB As New OleDbCommand
        Dim cmdInsert As New OleDbCommand
        Dim cmdUpdate As New OleDbCommand
        Dim cmdDelete As New OleDbCommand

        cnnOLEDB.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source =C:\Users\Jmcn\Desktop\GateTechDBTest.accdb"

        cnnOLEDB.Open()
        cmdUpdate.CommandText = "UPDATE Gtech SET Liability = @newdate WHERE [Gate Tech] = @tech" '& CInt(store)
        cmdUpdate.Parameters.AddWithValue("@tech", satech)
        cmdUpdate.Parameters.AddWithValue("@newdate", DateTimePicker1.Value.Date)
        cmdUpdate.CommandType = CommandType.Text
        cmdUpdate.Connection = cnnOLEDB
        cmdUpdate.ExecuteNonQuery()
        MsgBox("Record updated.")
        cmdUpdate.Dispose()
        cnnOLEDB.Close()
    Catch ex As Exception

    End Try
End Sub

结束班