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标题: asp.net 2.0中TREEVIEW中动态增加结点 [打印本页]

作者: 赵大宝 时间: 2012-10-29 18:28
标题: asp.net 2.0中TREEVIEW中动态增加结点
在asp.net 2.0中，要动态从数据库中取出内容，动态增加结点，其实不难，比如以SQL SERVER 2000的PUBS数据库为例子，要以树型列表方式，取出作者，做为根结点，然后取出每位作者写过什么书，作为子结点，可以这样

<％@ Page Language="C#"％>
<％@ Import Namespace="System.Data"％>
<％@ Import Namespace="System.Data.SqlClient"％>
<％@ Import Namespace="System.Configuration"％>

<!DOCTYPE htmlPUBLIC"-//W3C//DTD XHTML 1.1//EN""http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Dynamic Population of the TreeView Control</title>
<script runat=server>
void Node_Populate(object sender,
System.Web.UI.WebControls.TreeNodeEventArgs e)
{
if(e.Node.ChildNodes.Count == 0)
{
switch( e.Node.Depth )
{
case 0:
FillAuthors(e.Node);
break;
case 1:
FillTitlesForAuthors(e.Node);
break;
}
}
}

void FillAuthors(TreeNode node)
{
string connString = System.Configuration.ConfigurationSettings.
ConnectionStrings["NorthwindConnnection"].ConnectionString;
SqlConnection connection = new SqlConnection(connString);
SqlCommand command = new SqlCommand("Select * From
authors",connection);
SqlDataAdapter adapter = new SqlDataAdapter(command);
DataSet authors = new DataSet();
adapter.Fill(authors);
if (authors.Tables.Count > 0)
{
foreach (DataRow row in authors.Tables[0].Rows)
{
TreeNode newNode = new
TreeNode(row["au_fname"].ToString() + " " +
row["au_lname"].ToString(),
row["au_id"].ToString());
newNode.PopulateOnDemand = true;
newNode.SelectAction = TreeNodeSelectAction.Expand;
node.ChildNodes.Add(newNode);
}
}
}

void FillTitlesForAuthors(TreeNode node)
{
string authorID = node.Value;
string connString = System.Configuration.ConfigurationSettings.
ConnectionStrings["NorthwindConnnection"].ConnectionString;
SqlConnection connection = new SqlConnection(connString);
SqlCommand command = new SqlCommand("Select T.title,
T.title_id From titles T" +
" Inner Join titleauthor TA on
T.title_id = TA.title_id " +
" Where TA.au_id = '" + authorID + "'", connection);
SqlDataAdapter adapter = new SqlDataAdapter(command);
DataSet titlesForAuthors = new DataSet();
adapter.Fill(titlesForAuthors);
if (titlesForAuthors.Tables.Count > 0)
{
foreach (DataRow row in titlesForAuthors.Tables[0].Rows)
{
TreeNode newNode = new TreeNode(
row["title"].ToString(), row["title_id"].ToString());
newNode.PopulateOnDemand = false;
newNode.SelectAction = TreeNodeSelectAction.None;
node.ChildNodes.Add(newNode);
}
}
}

</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TreeViewRunat="Server" ExpandImageUrl="Images/closed.gif"
CollapseImageUrl="Images/open.gif"
OnTreeNodePopulate="Node_Populate" ID="tvwauthors">
<Nodes>
<asp:TreeNodeText="Authors" PopulateOnDemand=true
Value="0"/>
</Nodes>
</asp:TreeView>
</div>
</form>
</body>
</html>
其中，注意ontreenodepopulate事件，是在展开树的结点时发生的，这里定义了自定义的NODE_POPULATE,在node_populate中，检查当前结点的深度，如果是0，就是根结点，于是就调用FillAuthors过程，取出所有的作者，如果深度是1，则是叶子结点，调用FillTitlesForAuthors过程。其中，要注意它们中的动态建立树结点的过程，如：
TreeNode newNode = new TreeNode(row["au_fname"].ToString() + " " +
row["au_lname"].ToString(),

row["au_id"].ToString());

newNode.PopulateOnDemand = true;

newNode.SelectAction = TreeNodeSelectAction.Expand;

node.ChildNodes.Add(newNode);
其中， popluateondemand属性表明，该结点会动态扩展

作者: 许庭洲 时间: 2012-10-29 18:55
太值得学习ing!

作者: 赵大宝 时间: 2012-10-29 19:16

许庭洲发表于 2012-10-29 18:55
太值得学习ing!

{:3_49:} 。。。。。

作者: 郑鹏 时间: 2012-10-29 21:04
感觉看起来有点晕！下面是我自己做了一个新闻发布系统的后台管理项目菜单，遇到动态treeview，我是这么做的:
说明：我采用简单的三层架构来写的，带model的那种
1.首先在数据库先建表，然后建视图

这是model层代码，由于时间有点久，一时没找到，相信亲根据model也可以建出表和视图：
using System;
using System.Collections.Generic;
using System.Text;

namespace Model
{
public class viewUserRightInfo
{
      private string rolename;

      private int roleid;

      private int _funid;

      public int funid
      {
         get { return _funid; }
         set { _funid = value; }
      }
      private string _funname;

      public string funname
      {
         get { return _funname; }
         set { _funname = value; }
      }
      private string _funurl;

      public string funurl
      {
         get { return _funurl; }
         set { _funurl = value; }
      }

      private int _displayid;

      public int displayid
      {
         get { return _displayid; }
         set { _displayid = value; }
      }
      private int _fatherid;

      public int fatherid
      {
         get { return _fatherid; }
         set { _fatherid = value; }
      }
      private int userid;

      public int UserId
      {
         get { return userid; }
         set { userid = value; }
      }
      private string username;

      public string UserName
      {
         get { return username; }
         set { username = value; }
      }

      public int RoleId
      {
         get { return roleid; }
         set { roleid = value; }
      }

      public string RoleName
      {
         get { return rolename; }
         set { rolename = value; }
      }
}
}

2.DAL层代码

public class viewUserRightInfoService
{
      public static List<viewUserRightInfo> GetAllParentNodeInfoByUserId(int funid , int userid)
      {

         string sql = string.Format("select * from viewUserRightInfo where fatherid={0} and UserId ={1}",funid, userid);
         return datatables(sql);
      }

      public static List<viewUserRightInfo> select_by_roleid(int roleid)
      {
         string sql = string.Format("select * from viewUserRightInfo where  RoleId ={0}", roleid);
         return datatables(sql);
      }

      public static List<viewUserRightInfo> select_by_userid(int userid)
      {
         string sql = string.Format("select * from viewUserRightInfo where  UserId ={0}", userid);
         return datatables(sql);
      }
      public static viewUserRightInfo select_by_username(string username)
      {
         string sql = string.Format("select * from viewUserRightInfo where  UserName ='{0}'", username);
         return datarow(sql);
      }

      public static List<viewUserRightInfo> datatables(string sql)
      {
         List<viewUserRightInfo> list = new List<viewUserRightInfo>();
         viewUserRightInfo view = null;
         DataTable dt = SqlHelper.GetDataSet(sql);
         if (dt != null)
         {

            foreach (DataRow dr in dt.Rows)
            {
                  view = new viewUserRightInfo();
                  view.RoleName = (string)dr["RoleName"];
                  view.RoleId = (int)dr["roleid"];
                  view.funid = (int)dr["funid"];
                  view.funname = (string)dr["funname"].ToString();
                  view.funurl = (string)dr["funurl"].ToString();
                  view.displayid = (int)dr["displayid"];
                  view.fatherid = (int)dr["fatherid"];
                  view.UserId = (int)dr["UserId"];
                  view.UserName = (string)dr["UserName"].ToString();
                  list.Add(view);
            }
            return list;

         }
         else
         {
            return null;
         }

      }

      public static viewUserRightInfo datarow(string sql)
      {

         viewUserRightInfo view = null;
         DataRow dr = SqlHelper.GetDataSet(sql).Rows[0];
         if (dr != null)
         {
            view = new viewUserRightInfo();
            view.RoleName = (string)dr["RoleName"];
            view.RoleId = (int)dr["roleid"];
            view.funid = (int)dr["funid"];
            view.funname = (string)dr["funname"].ToString();
            view.funurl = (string)dr["funurl"].ToString();
            view.displayid = (int)dr["displayid"];
            view.fatherid = (int)dr["fatherid"];
            view.UserId = (int)dr["UserId"];
            view.UserName = (string)dr["UserName"].ToString();
            return view;
         }
         else
         {
            return null;
         }
      }

}

3.BLL层代码
public class viewUserRightInfoManager
{
      public static List<viewUserRightInfo> GetAllParentNodeInfoByUserId(int funid, int userid)
      {
         return viewUserRightInfoService.GetAllParentNodeInfoByUserId(funid, userid);
      }

      public static List<viewUserRightInfo> select_by_roleid(int roleid)
      {
         return viewUserRightInfoService.select_by_roleid(roleid);
      }

      public static List<viewUserRightInfo> select_by_userid(int userid)
      {
         return viewUserRightInfoService.select_by_userid(userid);
      }
      public static viewUserRightInfo select_by_username(string username)
      {
         return viewUserRightInfoService.select_by_username(username);
      }
}

4.后台代码

private TreeNode CreatTreaNode(string strText, int strId, string strUrl, string strImage)
{
      TreeNode newNode = new TreeNode();
      newNode.Text = strText.ToString();
      newNode.Value = strId.ToString();
      newNode.NavigateUrl = strUrl;
      newNode.ImageUrl = strImage;
      return newNode;
}

private void Display(User user)
{
      int roleid = (int)user.RoleId;

            TreeView1.Nodes.Clear();
            List<viewUserRightInfo> parent =viewUserRightInfoManager.GetAllParentNodeInfoByUserId(0, (int)user.UserId);
            foreach (viewUserRightInfo sf in parent)
            {
                  int nodeid = sf.funid;
                  string funname = sf.funname;
                  string image = "../Image/plugin_add.png";
                  TreeNode fatherNode = this.CreatTreaNode(funname, nodeid, "", image);
                  CreateChildTree(nodeid, (int)user.UserId, fatherNode);
                  TreeView1.Nodes.Add(fatherNode);
            }

      }

private void CreateChildTree(int nodeid, int userid, TreeNode fatherNode)
{

      List<viewUserRightInfo> child = viewUserRightInfoManager.GetAllParentNodeInfoByUserId(nodeid, userid);
      foreach (viewUserRightInfo sfchild in child)
      {
         int id = sfchild.funid;
         string childname = sfchild.funname;
         string nodeurl = ResolveUrl(sfchild.funurl.Trim());
         string image = "../Image/plugin_edit.png";
         TreeNode childNode = this.CreatTreaNode(childname, nodeid, nodeurl, image);
         CreateChildTree(id, userid, fatherNode);
         AddTree(fatherNode, childNode);
      }

}

private void AddTree(TreeNode fathernode, TreeNode chilenode)
{
      fathernode.ChildNodes.Add(chilenode);
}

      //List<Roleright> list = new List<Roleright>();
      //list = RolerightManager.select_by_roleid(roleid);
      //for (int i = 0; i < list.Count; i++)
      //{
      // int nodeid = list[i].Funid;
      // List<Funinfo> funlist = Funinfomessage.select_by_funid(nodeid);
      // for (int j = 0; j < funlist.Count; j++)
      // {

      //       TreeNode fathernode = CreatNode(funlist[j].Funname.ToString(), "");
      //       int fatherid = funlist[j].Funid;
      //       List<Funinfo> fulist = Funinfomessage.select_by_fatherid(fatherid);

      //       for (int e = 0; e < fulist.Count; e++)
      //       {

      //             TreeNode chilenode = CreatNode(fulist[e].Funname.ToString(), fulist[e].Funurl.ToString());

      //             fathernode.ChildNodes.Add(chilenode);

      //       }
      //       this.TreeView1.Nodes.Add(fathernode);

      // }

      //}

//}

private TreeNode CreatNode(string strtext, string strurl)
{
      TreeNode node = new TreeNode();
      node.Text = strtext;
      node.NavigateUrl = strurl;
      return node;
}
}       以上有什么问题和建议请回复，我一直都用这个很好用的，还可以对这些节点进行管理，增删改

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