VB arraylist訪問另一個類

Question

我正在爲一門課程編寫POS應用程序。我在訪問另一個類中的ArrayList類型的itemList時遇到問題。下面是我的兩個類的代碼。是否有可能在另一個類中訪問arrayList（即在Transaction之內）？

Public Class Item 

    'Declares item variables 
    Public itemName As String 
    Public itemPrice As Decimal 
    Public itemQty As Integer 
    Public itemSku As Long 
    Public itemList As New ArrayList 
    Public newItem As Item 


    'Method passes details of item 
    Public Sub AddItem(itemSku, itemName, itemPrice, itemQty) 
     itemSku = newItem.itemSku 
     itemName = newItem.itemName 
     itemPrice = newItem.itemPrice 
     itemQty = newItem.itemQty 
     itemList.Add(newItem) 'adds newItem to arrayList of items itemList 
    End Sub 


End Class 


Public Class Transaction 
    Dim subtotal As Decimal 
    Dim tax As Decimal 
    Dim total As Decimal 
    Dim paymentType As String 

    Public Function calculateBalance() 
     For count As Integer = 0 To itemList.Count 'TRYING TO ACCESS ARRAYLIST HERE 

     Next 
    End Function 
End Class 

Answer 1

的問題是，你不說明其itemList應使用Item類的實際實例。更改功能爲：

Public Function calculateBalance(myItem As Item) 
    For count As Integer = 0 To myItem.itemList.Count 'TRYING TO ACCESS ARRAYLIST HERE 

    Next 
End Function