Comment mettre à jour la base de données en utilisant datagridview (vb.net)

Voici mon code, mais sa l'autre sens, il valide les modifications apportées à la datagridview lorsque la base de données est mise à jour.

Imports System    
Imports System.Data    
Imports System.Data.OleDb    
Imports System.Windows.Forms
Public Class Form1    
Inherits System.Windows.Forms.Form
Private bindingSource1 As New BindingSource()    
Private dataAdapter As New OleDbDataAdapter()
<STAThreadAttribute()> _    
Public Shared Sub Main()    
Application.Run(New Form1())    
End Sub
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load    
Dim connectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\GRN.mdb;User Id=admin;Password=;"    
Dim selectCommand As String    
Dim connection As New OleDbConnection(connectionString)
selectCommand = "select * from GRNITEMS ORDER BY GRNNO, ITEMCODE"    
Me.dataAdapter = New OleDbDataAdapter(selectCommand, connection)
With DataGridView1    
.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.AllCells    
.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.ColumnHeader    
.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.ColumnHeader    
End With
Dim commandBuilder As New OleDbCommandBuilder(Me.dataAdapter)    
Dim table As New DataTable()
table.Locale = System.Globalization.CultureInfo.InvariantCulture
Me.dataAdapter.Fill(table)    
Me.bindingSource1.DataSource = table
Dim data As New DataSet()
data.Locale = System.Globalization.CultureInfo.InvariantCulture
DataGridView1.DataSource = Me.bindingSource1    
Me.DataGridView1.AlternatingRowsDefaultCellStyle.BackColor = Color.Aqua    
Me.DataGridView1.AutoResizeColumns( _    
DataGridViewAutoSizeColumnsMode.AllCells)
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim table As New DataTable()
Me.bindingSource1 = Me.DataGridView1.DataSource    
table = Me.bindingSource1.DataSource
Me.dataAdapter.Update(table)    
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Me.Close()   
End Sub
End Class