01.Function getcus() As Integer
02. If con.State = ConnectionState.Closed Then
03. con.Open()
04. End If
05. Try
06. Dim Ole As String = "SELECT MAX(Cus_id)FORM Customer"
07. Dim com As New OleDbCommand(Ole, con)
08.
09.
10. Dim max As Integer = com.ExecuteScalar
11. Return max + 1
12. Catch ex As Exception
13. Return 1001
14. End Try
15.
16.End Function
17.
18.Private Sub add_Click(sender As System.Object, e As System.EventArgs) Handles addButton.Click
19. Cus_IDTextBox.Text = "C" & getcus()
20.
21. Me.CustomerBindingSource.AddNew()
22. Call read()
23.
24. Cus_IDTextBox.Focus()
25.
26.End Sub
