WPF中TreeView控件实现动态加载节点

来源:转载

难得有空,呵呵,最近项目需要,使用一个树型控件,其实数据量不大,简单使用一次递归就可以完事,但话说回来,想想,当数据量达到一个量级时,这个方法明显就不足(程序运行十分不给力),而使用节点的深度特性实现加载控制,达到动态生成节点项的目的,这不失为一个好方法。

先来看看本实例的完成图(此处只实现其中动态加载功能,其实后续再补上):

 

技术点:

数据库结构:

 

其中Depth为节点深度

核心类TreeViewHelper代码(代码写得没水平请不要见笑,呵呵):

        public static void CreatTreeView(TreeView _myTreeView, myEx_TreeViewItem _parentNode, DataTable dt, bool isRoot = true, bool isActivity = true, int Depth = 3)

        {            string myFilterString = isRoot? "ParentID = 0":"ParentID = " + _parentNode.ID.ToString();
            if (isActivity)
            {
                #region 动态加载节点
                if (Depth > 0)
                {
                    foreach (DataRow row in dt.Select(myFilterString))
                    {
                        myEx_TreeViewItem item = new myEx_TreeViewItem();
                        item.ID = (int)row["ID"];
                        item.Depth = (int)row["Depth"];
                        item.ItemContent = row["NodeName"].ToString();
                        item.ParentID = (int)row["ParentID"];
                        item.ItemPath = row["NodePath"].ToString();
                        item.IconPath = row["IconPath"].ToString();
                        item.IsExpanded = false;
                        if (isRoot)
                        {
                            _myTreeView.Items.Clear();  //加载根节点前先清除Treeview控件项
                            item.IsExpanded = true;
                            _myTreeView.Items.Add(item); //新增根节点
                        }
                        else
                        {
                            item.IsExpanded = false;
                            _parentNode.Items.Add(item); //新增下级节点
                        }
                        CreatTreeView(_myTreeView, item, dt,false,true,Depth-1);                     }
                }
                #endregion
            }
            else
            {
                #region 递归生成树
                foreach (DataRow row in dt.Select(myFilterString))
                {
                    myEx_TreeViewItem item = new myEx_TreeViewItem();
                    item.ID = (int)row["ID"];
                    item.Depth = (int)row["Depth"];
                    item.ItemContent = row["NodeName"].ToString();
                    item.ParentID = (int)row["ParentID"];
                    item.ItemPath = row["NodePath"].ToString();
                    item.IconPath = row["IconPath"].ToString();
                    if (isRoot)
                    {
                        _myTreeView.Items.Clear();
                        item.IsExpanded = true;
                        _myTreeView.Items.Add(item); //新增根节点
                    }
                    else
                    {
                        item.IsExpanded = false;
                        _parentNode.Items.Add(item); //新增下级节点
                    }
                    CreatTreeView(_myTreeView, item, dt, false);
                }
                #endregion
            }
        }

 

 

        public static void CreatTreeViewItemChild(TreeView _myTreeView, myEx_TreeViewItem _SelectedParentItem, DataTable dt, int Depth = 2)
        {
                _SelectedParentItem.Items.Clear();

                if (Depth > 0)  //判断加载的深度,默认只加载两级
                {
                    //设定过滤条件
                    string myFilterString;
                    myFilterString = "ParentID = " + _SelectedParentItem.ID.ToString();

                    foreach (DataRow row in dt.Select(myFilterString))
                    {
                        myEx_TreeViewItem item = new myEx_TreeViewItem();
                        item.ID = (int)row["ID"];
                        item.Depth = (int)row["Depth"];
                        item.ItemContent = row["NodeName"].ToString();
                        item.ParentID = (int)row["ParentID"];
                        item.ItemPath = row["NodePath"].ToString();
                        item.IconPath = row["IconPath"].ToString();
                        item.IsExpanded = false;
                        _SelectedParentItem.Items.Add(item); //新增下级节点
                        CreatTreeViewItemChild(_myTreeView, item, dt, (Depth - 1));
                    }
                }
            }

有不足之处请指点,代码整理后再分享给大下,以下是程序的Demo,可看看实际效果,需要net4.0版本运行环境

源码下载

本文来自马路灯的博客,原文地址:http://www.cnblogs.com/netsutang/articles/2092971.html


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