At least, you can write out the repeating array access.
// Want to edit the value of the Item
Edit editbutton = new Edit();
var item = basket.Items[lst_Results.SelectedIndex];
editbutton.NameOfItem = item.ItemName;
editbutton.Quantity = item.Quantity;
editbutton.ReplacementValue = item.Price;
if (editbutton.ShowDialog() == DialogResult.OK)
{
basket.UpdateReplacementValue(item.ItemName, editbutton.Quantity, editbutton.ReplacementValue);
RenderLibrary();
}
Also, you might want to just pass the object as parameter to the control, and edit it there using data binding.