Subscribe to the lb.SelectedIndexChanged event.
tabpage tp = new tabpage;
form2.tabcontrol.tabpage.add(tp)
Listbox lb = new Listbox;
lb.SelectedIndexChanged += new EventHandler(lb_SelectedIndexChanged);
tp.controls.add(lb);
Once an item is clicked, you can get the selected indexes (or index):
<br />
void lb_SelectedIndexChanged(object sender, EventArgs e)<br />
{<br />
<pre><br />
ListBox lb = sender as ListBox;<br />
int selectedIndex = lb.SelectedIndex;<br />
System.Windows.Forms.ListBox.SelectedIndexCollection <br />
selectedCollection = lb.SelectedIndices;<br />
</pre><br />
}<br />
<br />