Private Sub Command1_Click()

Dim s, tu As String

Dim n, dem As Integer

s = txtnguon

tu = txtdtu

n = InStr(1, s, tu)

dem = 0

Do While n > 0

dem = dem + 1

s = Mid(s, n + Len(tu))

n = InStr(1, s, tu)

Loop

lbldem = "keát quaû:" & Str(dem)

End Sub

Private Sub Command2_Click()

txtnguon = " "

txtdtu = " "

lbldem = " "

End Sub

Private Sub Command3_Click()

Dim tl As String

tl = MsgBox("ban co muon thoat khong", vbQuestion + vbYesNoCancel, "bang thong bao")

If tl = vbYes Then

End

End If

End Sub