Question

我正在用一些Visual Basic方言编写脚本。我想制作递归函数但在内部我有消息说Object var什么都没有。当我尝试在main函数中获取对象时，一切正常但在输入Sub对象后什么都不是

Private Sub Search(ByRef draw As DrawingElements)
    For index0 = 0 To draw.Count
        Dim subDrawing As DrawingElement
        Set subDrawing = draw(index0)
        If subDrawing.DrawingElements.Count<>0 Then - Here I cannot Access Count because .DrawingElements Are nothing
            Search(subDrawing.DrawingElements)
        End If
        MsgBox(subDrawing.Type & " " & CStr(subDrawing.X) & " "& CStr(subDrawing.Y))
    Next
End Sub
Sub Main
    Dim App As Application
    Set App = New Application
    App.Show True
    With App.Packages(0).ActiveSheet
        Dim draw As DrawingElements
        Set draw = .DrawingElements
        Dim subDrawing As DrawingElement
        Set subDrawing =draw(0)
        MsgBox(CStr(subDrawing.DrawingElements.Count)) - Here I can acces Count and DrawingElements

        Search(.DrawingElements)
    End With
End Sub

我不熟悉Visual Basic，所以我不知道该怎么做。我尝试了ByRef和ByVal，我也有同样的结果。

Answer 1

我用Google搜索“DrawingElements”但没有点击。使用Set App = New Application，您可以创建一种或另一种显然具有Package和ActiveSheet的应用程序。

但是好的。显然，该工作表具有DrawingElements的集合，每个元素（DrawingElement）可以包含其他DrawingElements集合。但某处必须停止，然后该集合将为空，即其值为Nothing。尝试：

If (subDrawing.DrawingElements Is Nothing) Then   ' end of recursion

Answer 2

在VBA中，对象集合通常是从1开始的，而不是从0开始的：

For index0 = 1 To draw.Count

以及

With App.Packages(1).ActiveSheet

和

Set subDrawing =draw(1)

VB Object var在递归中没什么

2 个答案: