Excel VBA作为全局变量的问题

Question

我有UserForm，我用它来快速输入数据。当UserForm初始化时，为不同的宏分配了一些快捷方式。其中一个宏从我的数据表中删除整行。应该使用另一个宏来恢复这种删除。为此，我使用范围作为全局变量来备份删除。但是，范围不在范围内。

请参阅相关代码段和错误：

表单代码：

Public Sub UserForm_Initialize()

    'set shortcuts
    '...

    Application.OnKey "{BACKSPACE}", "delete_row"
    Application.OnKey "^z", "redo_row"
    '...

    '<curRow> is global variable (in Module1) which is needed for PicBro Userform..
    curRow = ActiveCell.Row

    '...       
End Sub

---

Private Sub UserForm_QueryClose(Cancel As Integer, CloseMode As Integer)

    '...

    'release shortcuts
    Application.OnKey "{BACKSPACE}"
    Application.OnKey "^z"
    '...

End Sub

第1单元代码：

'global variables in module1
'****************************
Public curRow As Long
Public rngBU As Range
'**************************** 
Public Sub delete_row()

    '...
    Set rngBU = Data.Rows(curRow)
    MsgBox "Copied row " & rngBU.Row & " for backup.."

    Data.Rows(curRow).delete Shift:=xlUp
    Data.Cells(curRow, 1).Activate

    '...
End Sub

---

Public Sub redo_row()
    MsgBox "Restoring deleted row " & rngBU.Row & " from backup.." 'ERROR runtime 424
    rngBU.Copy
    Data.Rows(curRow).Insert Shift:=xlDown
End Sub