ランダムパス生成

        Dim wk_buf As String = ""
        Dim wk_num As Single

        Do Until Len(wk_buf) = 8
            Randomize()
            wk_num = Int((122 * Rnd()) + 1)
            Select Case wk_num
                '記号等の排除
                Case Is < 49
                Case 58, 59, 60, 61, 62, 63, 64
                Case 91, 92, 93, 94, 95, 96
                    '誤認候補の排除
                Case 48, 49, 79, 108
                Case Else
                    wk_buf = wk_buf & Chr(wk_num)
            End Select
        Loop

        passwd.Text = wk_buf