何时需要在VBA中释放对象

Question

在查看这段代码时(为了简化这个问题，大部分代码都被删除了)，我开始想知道是否需要处理我使用的集合或类。

Option Explicit    
Private terminals As Collection

Sub BuildTerminalSummary()
  Dim terminal As clsTerminal
  Call LoadTerminals
  For Each terminal in terminals
  ...Do work here
  Next terminal

  Set terminals = Nothing

End Sub

Private Sub LoadTerminals()
  Do
    Set terminal = New clsTerminal

    ...Do work here

    'Add terminal to terminals collection
    terminals.Add terminal, key

  Loop Until endCondition
End Sub

在处理VBA时，我应该在什么时候释放对象(如果有的话)？

Answer 1

在我看来，您似乎将终端集合的作用域放在了错误的位置。让LoadTerminals返回创建终端集合：-

Option Explicit    

Sub BuildTerminalSummary()

  Dim terminals As Collection
  Dim terminal As clsTerminal

  Set terminals = LoadTerminals

  For Each terminal in terminals
  ...Do work here
  Next terminal

End Sub

Private Function LoadTerminals() As Collection
  Dim terminals As Collection : Set terminals = New Collection
  Do
    Set terminal = New clsTerminal

    '' # ...Do work here

    terminals.Add terminal, key

  Loop Until endCondition

  Set LoadTerminals = terminals

End Function

只要你有变量，就不需要特别地“处置”它们(我猜你的意思是将Nothing赋值给持有对它们的引用的变量。