vb怎样连接数据库

Option Explicit
Public appdisk As String
Public conn As New ADODB.Connection
Public Rs As New ADODB.Recordset
Public db As String
Private sSQL As String

Private Sub Form_Load()
Dim i As Integer

On Error GoTo Err

appdisk = Trim(App.Path)
If Right(appdisk, 1) <> "\" Then appdisk = appdisk & "\"
db = appdisk
db = "Provider=Microsoft.Jet.OLEDB.4.0;Persist Security Info=False;Data Source=" & db & "alex.mdb"
conn.CursorLocation = adUseClient
conn.Open db
Rs.Open "select * from aaa", conn, adOpenKeyset, adLockPessimistic

If Rs.EOF = False Then

Do Until Rs.EOF
Combo1.AddItem Rs!seqno, i
Rs.MoveNext
i = i + 1
Loop

End If

Rs.MoveFirst
dB_RsToCSVFile Rs, "T