C#

public enum Color
    {
     Any,
     D+, 
     D, 
     D-, 
     E+ 
    };

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if (dat.Tables["SQL Temp Table"].Rows.Count > 0)
                        foreach (DataRow dataRow in dat.Tables[0].Rows)
                        {
                            ListViewItem item = new ListViewItem();
                            item.Text = dataRow[0].ToString() + "- " + dataRow[1].ToString();
                            listView1.Items.Add(item);
// Set the view to show details.
    listView1.View = View.Details;
    // Allow the user to edit item text.
    listView1.LabelEdit = true;
    // Allow the user to rearrange columns.
    listView1.AllowColumnReorder = true;
    // Display check boxes.
    listView1.CheckBoxes = true;
    // Select the item and subitems when selection is made.
    listView1.FullRowSelect = true;
    // Display grid lines.
    listView1.GridLines = true;
    // Sort the items in the list in ascending order.
    listView1.Sorting = SortOrder.Ascending;
.
.
.                       }

[XmlRoot]
public class AList
{
   public List<B> ListOfBs {get; set;}
}

public class B
{
   public string BaseProperty {get; set;}
}

public class C : B
{
    public string SomeProperty {get; set;}
}

public class Main
{
    public static void Main(string[] args)
    {
        var aList = new AList();
        aList.ListOfBs = new List<B>();
        var c = new C { BaseProperty = "Base", SomeProperty = "Some" };
        aList.ListOfBs.Add(c);

        var type = typeof (AList);
        var serializer = new XmlSerializer(type);
        TextWriter w = new StringWriter();
        serializer.Serialize(w, aList);
    }    
}

TypeDescriptor.AddAttributes(typeof(AList), new[] { new XmlIncludeAttribute(c.GetType()) });

var type = typeof (AList);