當列表很長時，VB6列表循環不起作用

Question

如何使VB6列表計數對超過32767項目的列表工作？

for k = 0 to List2.ListCount - 1 
''do stuff 
next 

上面的代碼的偉大工程，直到我在我的名單有太多的項目，然後列表計數得到所有擰緊和變負。

我該如何解決這個問題？我可以讓ListCount成爲一個長數據類型嗎？

Answer 1

雖然VB6屬性只籤Integer底層控制採用32個整數，所以你可以使用Windows API來操縱你的列表：

Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long 
Private Declare Function SendMessageString Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As String) As Long 
Private Const LB_GETCOUNT = &H18B 
Private Const LB_GETTEXT = &H189 
Private Sub Command1_Click() 
    Dim ix As Long 
    For ix = 0 To 40000 
     List1.AddItem "X" + Format(ix) 
    Next 
End Sub 

Private Sub Command2_Click() 
    Dim rc As Long 
    Dim wp As Long 
    Dim lp As Long 
    Dim s As String * 1000 
    ' Get count of items into rc 
    rc = SendMessage(List1.hwnd, LB_GETCOUNT, 0, 0) 
    ' Get the 39001th item 
    rc = SendMessageString(List1.hwnd, LB_GETTEXT, 39000, s) 
    MsgBox s 
End Sub 

話雖如此切換到ListView仍然可能是一個好理念。