Private bindingSource As BindingSource
    Private ta1Table As DataTable
 
Private Sub LadeDaten(ByVal selectString As String, ByVal connStr As String)
        Dim adap As New OleDb.OleDbDataAdapter(selectString, connStr)
        ta1Table = New DataTable("ta1")
        adap.Fill(ta1Table)
        bindingSource = New BindingSource()
        bindingSource.DataSource = ta1Table
        Me.RichTextBox1.DataBindings.Add("Text", bindingSource, "Test3")
    End Sub

 
Private Sub Suchen()
        Dim pos As Integer = bindingSource.Find("Test", TextBox1.Text)
        If (pos <> -1) Then
            bindingSource.Position = pos
        End If
    End Sub

 
    Private Sub SchreibeDaten(ByVal selectString As String, ByVal connStr As _
      String)
        Dim adap As New OleDb.OleDbDataAdapter(selectString, connStr)
        Dim cb As New OleDb.OleDbCommandBuilder(adap)
        bindingSource.EndEdit()
        adap.Update(ta1Table)
    End Sub