|
Add ListBox Items
The .NET Framework lets you associate any type of value with a ListBox row.
by Fabio Claudio Ferracchiati and Jimmy Nilsson
Posted October 7, 2003
Technology Toolbox: VB.NET, SQL Server 2000
Q. Add ListBox Items
When I use VB6 and a ListBox (or a ComboBox), I can use the ItemData property to associate a value with a row different from the value that's displayed. However, ItemData isn't available in VB.NET. How can I perform the same operation?
A.
You can add an item to a ListBox (or ComboBox) list in VB.NET by using the Items property's Add method, which returns a reference to the ObjectCollection class. As this class's name implies, the ListBox can contain a collection of Object objects, so you're not constrained (as you are with ItemData and VB6) to associate only an integer value with the ListBox item. The Object class is the base class for each .NET Framework class, so you can associate practically any kind of information with the ListBox item.
A ListBox that shows DataSet rows is a typical example. Suppose you use VS.NET 2003 to create an empty strongly typed DataSet (select Project | Add New Item, then select DataSet from the templates list) and add three columns: ID, FIRST_NAME, and LAST_NAME. The Form class's Load event fills the DataSet and adds the new row to the ListBox:
Private Sub frmMain_Load(_
ByVal sender As System.Object, _
ByVal e As System.EventArgs) _
Handles MyBase.Load
Dim ds As New Dataset1
Dim r As Dataset1.EMPLOYEERow = _
ds.EMPLOYEE.NewEMPLOYEERow()
r.ID = 1
r.FIRST_NAME = "Fabio Claudio"
r.LAST_NAME = "Ferracchiati"
ds.EMPLOYEE.AddEMPLOYEERow(r)
lbMain.Items.Add(r)
End Sub
Back to top
|