protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                SqlConnection sqlconncgtiontree = new SqlConnection();
                sqlconncgtiontree.ConnectionString = SqlCommon.ConnectionStringLocalTransaction.ToString();
                sqlconncgtiontree.Open();
                SqlDataAdapter sqlda = new SqlDataAdapter("select ColumnsID,ColumnsName,ParentID from Columns", sqlconncgtiontree);
                DataSet DataSet_Tree = new DataSet();
                sqlda.Fill(DataSet_Tree);
                this.ViewState["DataSet_Tree"] = DataSet_Tree;
                 AddTree(0, (TreeNode)null);
               
                sqlconncgtiontree.Close();
            }

        }

        protected void btnSave_Click(object sender, EventArgs e)
        {
            UserAdmin_System uas = new UserAdmin_System();
            uas.Add_UserAdmin(this.tbUserName.Text,BLL.SMJY.Common.MD5.Lower32(this.tbUserPsd.Text),this.tbTureName.Text,this.TextBox1.Text,1);

           BasicPage.FinalMessage("成功保存", "close.htm", 0);

        }
        public void AddTree(int ParentID, TreeNode pNode)
        {
            DataSet DataSet_Tree = (DataSet)this.ViewState["DataSet_Tree"];
            DataView DataView_Tree = new DataView(DataSet_Tree.Tables[0]);
            DataView_Tree.RowFilter = "[ParentID]=" + ParentID;


            foreach (DataRowView Row in DataView_Tree)
            {
                TreeNode Node = new TreeNode();
                if (pNode == null)
                {
                    Node.Text = Row["ColumnsName"].ToString();
                    
                    ColumnsTree.Nodes.Add(Node);
                    Node.Expanded = true;
                    AddTree(Int32.Parse(Row["ColumnsID"].ToString()), Node);
                }
                else
                {
                    Node.Text = Row["ColumnsName"].ToString();
                   //pNode.ChildNodes.Add(Node);
                    ColumnsTree.Nodes.Add(Node);

                    Node.Expanded = true;
                    AddTree(Int32.Parse(Row["ColumnsID"].ToString()), Node);
                }
            }
            
        }

 <asp:TreeView ID="ColumnsTree" runat ="server" ImageSet="XPFileExplorer" 
                NodeIndent="15">
               <HoverNodeStyle Font-Underline="True" ForeColor="#6666AA" />
               <NodeStyle Font-Names="Tahoma" Font-Size="8pt" ForeColor="Black" 
                   HorizontalPadding="2px" NodeSpacing="0px" VerticalPadding="2px" />
               <ParentNodeStyle Font-Bold="False" />
               <SelectedNodeStyle BackColor="#B5B5B5" Font-Underline="False" 
                   HorizontalPadding="0px" VerticalPadding="0px" />
               
            </asp:TreeView>