• asp.net中TreeView的大数据加载速度优化


    由于数据量太大,加载树时间很长,所以进行了优化

    前台 .aspx

       <asp:Panel ID="Panel2" runat="server" Height="600px" ScrollBars="Auto">
                            <asp:TreeView ID="TreeView1" runat="server" ForeColor="Black" OnTreeNodeExpanded="TreeView1_TreeNodeExpanded" OnSelectedNodeChanged="TreeView1_SelectedNodeChanged">
                                <LeafNodeStyle HorizontalPadding="3px" />
                                <ParentNodeStyle HorizontalPadding="3px" />
                                <RootNodeStyle HorizontalPadding="3px" />
                                <SelectedNodeStyle ForeColor="#009933" />
                            </asp:TreeView>
                        </asp:Panel>

    后台.cs 

      #region wsw更改树的加载方式
        private void LoadNewTree()
        {
            DataTable dtp = pagBLL.GetList(" superfuncid=0  order by sort asc").Tables[0];
            if (dtp.Rows.Count > 0)
            {
                //首先清除树型控件内的结点
                this.TreeView1.Nodes.Clear();
                for (int i = 0; i < dtp.Rows.Count; i++)
                {
    
                    //实例出一个结点
                    TreeNode Node = new TreeNode();
                    Node.Text = dtp.Rows[i]["funcname"].ToString();
                    Node.Value = dtp.Rows[i]["pagefuncid"].ToString();
                    Node.ToolTip = dtp.Rows[i]["funcurl"].ToString();
                    Node.ImageUrl = "../../" + dtp.Rows[i]["imageurl"].ToString(); 
                    this.TreeView1.Nodes.Add(Node);//增加父节点,这时直接往树TreeView1上加
                    this.LoadAddSign(Node.ChildNodes,Convert.ToInt32(dtp.Rows[i]["pagefuncid"].ToString()));//wsw更改
                    TreeView1.CollapseAll();
    
                }
            }
        }
        /// <summary>
        /// 用于加载显示 树形控件 +号的,加载下面的一个节点。
        /// </summary>
        /// <param name="Conn"></param>
        /// <param name="tn"></param>
        /// <param name="DeptId"></param>
        private void LoadAddSign( TreeNodeCollection tn, int DeptId) //wsw更改
        {
            DataTable table = pagBLL.GetList(" superfuncid=" + DeptId + "  order by sort asc").Tables[0];
            if (table.Rows.Count > 0)
            {
                //加载"一个"1级节点,就是为了显示 + 号
                tn.Add(new TreeNode());
    
            }
        }
        /// <summary>
        /// 点击 + 号是节点展开事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void TreeView1_TreeNodeExpanded(object sender, TreeNodeEventArgs e)
        {
            TreeNode node = e.Node;
            if (node.Expanded == true)
            {
                string bm = e.Node.Value.ToString();//wsw更改
                DataTable table = pagBLL.GetList(" superfuncid=" + bm + "  order by sort asc").Tables[0];
    
                node.ChildNodes.Clear(); //清除之前加载的空节点。
                if (table.Rows.Count > 0)
                {
                    for (int i = 0; i < table.Rows.Count; i++)
                    {
                        TreeNode Node = new TreeNode();
                        Node.Text = table.Rows[i]["funcname"].ToString();
                        Node.Value = table.Rows[i]["pagefuncid"].ToString();
                        Node.ToolTip = table.Rows[i]["funcurl"].ToString();
                        Node.ImageUrl = "../../" + table.Rows[i]["imageurl"].ToString();
                        node.ChildNodes.Add(Node);//增加父节点,这时直接往树TreeView1上加
                        this.LoadAddSign(Node.ChildNodes, Convert.ToInt32(table.Rows[i]["pagefuncid"].ToString()));//wsw更改
                    }
    
                }
            }
    
        }
        #endregion

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  • 原文地址:https://www.cnblogs.com/smile-wei/p/3930771.html
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