Asp:ListBox and selectedindex

[John Giblin]

I have a ListBox within a repeater tag and I am trying to set the selected
value. I tried the following without success. I was also tryng to make a
method for the selectedindex but I do not know how to pass the instance of
this asp:listbox control.

<asp:ListBox id="ListBox1" name="ListBox1" DataSource='<%#
GetDropDownQuantities( (BasketLine)DataBinder.Eval(Container,"DataItem"))
%>'
Rows="1"
CssClass="orderselect"
SelectionMode=Single
runat="server">
</asp:ListBox>
public ListItemCollection GetDropDownQuantities( BasketLine bl)
{
ListItemCollection listBoxData = new ListItemCollection();

int x=0;
bool isSelected = false;
while (x++ < 20)
{
ListItem li = new ListItem();
li.Value = x.ToString();
li.Text = x.ToString();
if (x==bl.Quantity && !isSelected)
{
li.Selected = true;
isSelected = true;
}
listBoxData.Add(li);

}
return listBoxData;
}

thanks

John