This example might help you.
Please enhance this code as per your requirement.
string[] items = { "1.1", "1.2", "1.1.1", "1.2.1", "1.1.2", "1.2", "1.2.1", "1.22.11", "1.3", "1.4" };
DataTable dtItem = new DataTable();
dtItem.Columns.Add("tab_index", typeof(string));
foreach (string item in items)
{
dtItem.Rows.Add(item);
}
dtItem.AcceptChanges();
DataView dvItem = dtItem.DefaultView;
dvItem.Sort = "tab_index";
foreach (DataRowView viewItem in dvItem)
{
System.Diagnostics.Debug.WriteLine(viewItem["tab_index"].ToString());
}