关闭表单时出现 VBA 自动化错误 - "server [not server application]"

Question

我尝试以面向对象的方式创建表单，如以下答案所示:https://stackoverflow.com/a/38382104/4460023 。关闭表单后，我想引用对象属性 IsCancelled 来检查调用子例程是否应继续执行。但是，当我在表单之外检查此属性时，遇到以下错误:

"Run-time error '-2147418105': Automation error. The callee (server [not server application]) is not available and disappeared; all connections are invalid. The call may have executed."

我猜这与关闭表单有关。作为替代解决方案，我只需写入存储在调用子模块中的全局变量即可。但理想情况下，我想使用此表单对象中的属性。我的代码如下:

在表单内:

Private cancelling As Boolean

Public Property Get IsCancelled() As Boolean
    IsCancelled = cancelling
End Property

Private Sub UserForm_QueryClose(Cancel As Integer, CloseMode As Integer)
    If CloseMode = VbQueryClose.vbFormControlMenu Then
        cancelling = True
    End If
End Sub

然后在调用子例程中:

Set frm = New ViewByWorkerForm
frm.Show

If frm.IsCancelled Then 'error happens here
    Exit Sub
End If

请注意，当我不关闭表单时，我可以在类中使用其他字符串属性 - 只有表单关闭才会触发此问题。

Answer 1

修复您的代码

Private Sub UserForm_QueryClose(Cancel As Integer, CloseMode As Integer)
    If CloseMode = VbQueryClose.vbFormControlMenu Then
        Cancel = True
    End If
    Hide
    cancelling = True
End Sub