Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        Dim arr As New ArrayList
        Me.Text = "search.."
        Me.GetFiles("C:\", "*.mp3", arr)
        Me.ListBox1.Items.AddRange(CType(arr.ToArray(GetType(String)), String( _
          )))
        Me.Text = "done"
    End Sub
    Private Sub GetFiles(ByVal path As String, ByVal pattern As String, ByRef _
      arr As ArrayList)
        Try
            arr.AddRange(IO.Directory.GetFiles(path, pattern))
            For Each s As String In IO.Directory.GetDirectories(path)
                GetFiles(s, pattern, arr)
                If arr.Count Mod 4 Then Application.DoEvents()
            Next
        Catch ex As Exception
            Debug.WriteLine(ex.ToString)
        End Try
    End Sub