private void BindTreeView()
    {
        UnitInfo bUnitInfo = new UnitInfo();
        DataSet ds = bUnitInfo.GetUnitInfo();
        if (ds != null && ds.Tables[0].Rows.Count > 0)
        {
            bool HasAddedLast = true; ;
            string strDs = "<?xml version='1.0' encoding='GB2312'?>";
            for (int i = 1; i < ds.Tables[0].Rows.Count; i++)
            {
                strDs += "<a Name='" + ds.Tables[0].Rows[i-1][1].ToString() + "' TID='" + ds.Tables[0].Rows[i-1][0].ToString() + "'>";
                for (int j = i; j < ds.Tables[0].Rows.Count; j++)
                {
                    i = j;
                    if (ds.Tables[0].Rows[j-1]["Path"].ToString().Length == ds.Tables[0].Rows[j]["Path"].ToString().Length)
                    {
                        strDs += "</a><a Name='" + ds.Tables[0].Rows[j][1].ToString() + "' TID='" + ds.Tables[0].Rows[j][0].ToString() + "'>";
                    }
                    else if (ds.Tables[0].Rows[j -1]["Path"].ToString().Length < ds.Tables[0].Rows[j]["Path"].ToString().Length)
                    {
                        strDs += "<a Name='" + ds.Tables[0].Rows[j][1].ToString() + "' TID='" + ds.Tables[0].Rows[j][0].ToString() + "'>";
                    }
                    else
                    {
                        if (i==ds.Tables[0].Rows.Count-1)
                        {
                            HasAddedLast = false;
                        }
                        break;
                    }
                }
                int nCount = 0;
                nCount = System.Math.Abs(ds.Tables[0].Rows[i - 1]["Path"].ToString().Length - ds.Tables[0].Rows[i]["Path"].ToString().Length) / 5 + 1;
                for (int j = 0; j < nCount; j++)
                {
                    strDs += "</a>";
                }
                if ((i == ds.Tables[0].Rows.Count - 1) && HasAddedLast==false)
                {
                    strDs += strDs += "<a Name='" + ds.Tables[0].Rows[i][1].ToString() + "' TID='" + ds.Tables[0].Rows[i][0].ToString() + "'>";
                    for (int k = 0; k < (ds.Tables[0].Rows[i]["Path"].ToString().Length/5-1); k++)
                    {
                        strDs += "</a>";
                    }
                }
            }
            strDs += "</a>";
            XmlDataSource xds = new XmlDataSource();
            xds.ID = "XDS";
            xds.Data = strDs;
            TreeView1.DataSource = xds;
            TreeView1.DataBind();
        }
    }

这个算法没有经过大量数据的检验，有待考证！