不懂就问

'如果变量只在当前模块中使用也可以用dim来定义，不过一般都会全局变量来定义的
Option Explicit
Public dic As Object, arr
Sub first()
　Dim i As Long
　Set dic = CreateObject("scripting.dictionary")
　ReDim arr(9)
　For i = LBound(arr) To UBound(arr)
　　dic(i) = i
　　arr(i) = i
　Next
End Sub
Sub second()
　If dic Is Nothing Then
　　MsgBox "!"
　Else
　　MsgBox "dic:" & Join(dic.Keys, ",") & vbNewLine & "arr:" & Join(arr, ",")
　End If
End Sub
Sub reset()
　Set dic = Nothing
　arr = ""
End Sub