Option Explicit
Private m_Cancel As Boolean

Private Sub Command1_Click()
    Dim lFilesCopied As Long
    lFilesCopied = ZCopy("c:\temp", "d:\mytemp", _
        "*.*", m_Cancel)
End Sub

Private Sub Command2_Click()
    m_Cancel = True
End Sub

Private Function ZCopy(FromDir$, ToDir$, Filter$, _
    Optional Cancel As Boolean = False) As Long
    Dim szResult As String
    Dim lCounter As Long
    On Error GoTo OOPS
    FromDir = FromDir & IIf(Right$(FromDir, 1) = "\", "", "\")
    ToDir = ToDir & IIf(Right$(ToDir, 1) = "\", "", "\")
    szResult = Dir$(FromDir & Filter)
    Do While Len(szResult) > 0
        If m_Cancel Then
            m_Cancel = False
            Exit Do
        End If
        DoEvents
        Call FileCopy(FromDir & szResult, ToDir & szResult)
        szResult = Dir$
        lCounter = lCounter + 1
    Loop
    ZCopy = lCounter
    Exit Function
OOPS:
    ZCopy = -9999
End Function