'This should only be called at the end of list
    indent_testcases = 0
End Function
Private Sub 分级_Click()
    ActiveSheet.UsedRange.ClearOutline
   
    With ActiveSheet.Outline
        .AutomaticStyles = False
        .SummaryRow = xlAbove
        .SummaryColumn = xlRight
    End With
   
    Dim r As Object
    Set r = ActiveSheet.UsedRange

    Call indent_testcases(r, r.Rows.Row + 1)

  
'    ActiveSheet.Outline.ShowLevels RowLevels:=2
End Sub

Private Sub 取消分级_Click()
    ActiveSheet.UsedRange.ClearOutline
End Sub

创建"下拉列表"
  选择数据区域-->执行"数据/有效性"命令->打开"数据有效性"对话框->单击"设置"选项卡->在"允许"栏选择"序列","来源"中输入数据(不含引号,用英文单引号分隔)->单击"确认"

修改"下拉列表"
  前提条件是确保"工具->保护"没有对表单保护,然后选择"有效性",查看"来源"框里序列的引用.在"工具->宏->VB编辑器"查找相应的变量，然后再找到下拉框内容对应的表单名，最后在“格式->工作表->取消隐藏”中选择对应的表单名，然后就可以直接修改了！
Option Explicit

Function indent_testcases(ByRef r As Range, ByVal startrow As Integer) As Integer
    Dim level, grouplevel, i
   
    grouplevel = Len(r.Cells(startrow, 1))
      
    i = startrow
    'Count = 0
    While i <= r.Count
    'While i <= 100
        level = Len(r.Cells(i, 1))
       
        If level = grouplevel Then
            i = i + 1
        ElseIf level > grouplevel Then
            'recursively call
            i = indent_testcases(r, i)
            If i <= 0 Then Exit Function
        Else
            Debug.Print "Group: " & CStr(startrow) & " - " & CStr(i - 1)
            If Not (level = 0 And startrow = 2) Then
            Rows(CStr(startrow) & ":" & CStr(i - 1)).Group
            End If

            indent_testcases = i
            Exit Function
        End If
    Wend