获得VB listbox 选中项目(多项)的一个好方法

传统方法是遍历一遍
如果listbox 项目过多
明显速度不行
好方法是通过sendmessge发消息给listbox让他把选中项目直接传到参数数组中
You can use the SendMessage() API function instead.
As
you probably know, this function lets you send a message to one or more
windows. The declaration statement conforms to the following syntax:
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
Since
we want to gather the listbox: selected items, we'll send the
LB_GETSELITEMS constant in the wMsg argument, which you declare like so:
Private Const LB_GETSELITEMS = &H191
The LB_GETSELITEMS message fills an array with the index numbers of all the selected items.
Dim ItemIndexes() As Long, x As Integer, iNumItems As Integer
iNumItems = ThisBox.SelCount
If iNumItems Then
   ReDim ItemIndexes(iNumItems - 1)
   SendMessage ListBox1.hwnd, LB_GETSELITEMS, iNumItems, ItemIndexes(0)
End If
For x = 0 To iNumItems - 1
   MsgBox ListBox1.List(ItemIndexes(x)) '弹出对话框
Next x
After
being passed to the SendMessage function, iNumItems holds the total
number of selected items, and the ItemIndexes array holds the selected
item index values. Notice, that you must pass a pointer to the
ItemIndexes array, and not the array itself. Thus, we passed
ItemIndexes(0) into the SendMessage function, not ItemIndexes().