Question

我正在使用VB.Net创建一个Windows应用程序。 SQLite数据库。在我的一个win形式中，我曾经通过单个事件下的单独SQL命令从两个表（ImpShpHeader，ImpShpDetail）中检索数据。 ImpShpHeader在ImpShpDetail中检索DataGridView中的数据并使用按钮单击事件使用两个单独的SQL命令更新两个表时，文本框中的数据检索一个命令是从文本框更新为ImpShpHeader但我正在使用DataGridView从ImpshpDetail更新为CommandBuilder。从文本框更新到ImpShpHeader是成功的，但CommandBuilder更新会出现以下错误：多个基表不支持动态SQL生成。所以这里我需要手动SQL命令来更新任何DataGridView中的更改。这是我的代码：

'TO RETRIEVE DATA FROM TABLES
Private Sub txtContainerNo_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles txtContainerNo.KeyDown
    If e.KeyCode = Keys.Enter Then
        Try
            con.Open()

            cmdString = "SELECT * FROM ImpShpHeader WHERE container = '" & txtContainerNo.Text & "'"
            ImpShpHeaderDA = New SQLiteDataAdapter(cmdString, con)
            ImpShpHeaderDA.Fill(ImpShpHeaderDT)

            txtContainer.Text = ImpShpHeaderDT.Rows(0).Item("container").ToString
            txtContainer.Enabled = False
            txtShipper.Text = ImpShpHeaderDT.Rows(0).Item("shipper").ToString
            txtPackages.Text = ImpShpHeaderDT.Rows(0).Item("packages").ToString
            txtETA.Text = ImpShpHeaderDT.Rows(0).Item("eta").ToString

            cmdString = "SELECT item, description, shipqty FROM ImpShpDetail WHERE container = '" & txtContainer.Text & "'"
            ImpShpDetailDA = New SQLiteDataAdapter(cmdString, con)
            ImpShpDetailDA.Fill(ImpShpDetailDT)
            dgvImpShpDetail.DataSource = ImpShpDetailDT

            'STYLE AND APPEARENCE OF DATA GRID VIEW
            dgvImpShpDetail.Columns(0).HeaderText = "Item No."
            dgvImpShpDetail.Columns(1).HeaderText = "Description"
            dgvImpShpDetail.Columns(2).HeaderText = "Ship Qty"

            dgvImpShpDetail.RowHeadersVisible = False

            dgvImpShpDetail.AutoSizeColumnsMode = DataGridViewAutoSizeColumnMode.DisplayedCells

            dgvImpShpDetail.Columns(0).DefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter
            dgvImpShpDetail.Columns(1).DefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleLeft
            dgvImpShpDetail.Columns(2).DefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter

        Catch ex As Exception
            MsgBox("Ann error occured!" & vbCrLf & vbCrLf & ex.Message)
        End Try
        con.Close()
    End If
End Sub

'TO UPDATE MULTIPLE TABLES
Private Sub btnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click
    dlgResult = MessageBox.Show("Do you want to save the changes?", "Confirmation", MessageBoxButtons.YesNo)
    If dlgResult = DialogResult.Yes Then
        Try
            con.Open()

            cmdString = "UPDATE ImpShpHeader SET container = @container, shipper = @shipper, packages = @packages, eta = @eta WHERE container = '" & txtContainer.Text & "'"

            cmd = New SQLiteCommand(cmdString, con)

            cmd.Parameters.Add("@container", SqlDbType.VarChar).Value = txtContainer.Text
            cmd.Parameters.Add("@shipper", SqlDbType.VarChar).Value = txtShipper.Text
            cmd.Parameters.Add("@packages", SqlDbType.VarChar).Value = txtPackages.Text
            cmd.Parameters.Add("@eta", SqlDbType.VarChar).Value = txtETA.Text

            cmd.ExecuteNonQuery()

            cmdbl = New SQLiteCommandBuilder(ImpShpDetailDA)
            ImpShpDetailDA.Update(ImpShpDetailDT)

            MsgBox("Updated successfully!")

        Catch ex As Exception
            MsgBox("An error occured!" & vbCrLf & vbCrLf & ex.Message)
        End Try
        con.Close()
    End If
End Sub

如何在不使用CommandBuilder的情况下在VB.Net中编写手动SQL命令以从DataGridView更新

0 个答案: