TreeView控件的绑定

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using MySql.Data.MySqlClient;
using System.Data;
public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            DataTable dtFather=exe_Table("server=localhost;user id=root;password=root;database=em", "select distinct tb_category.category_id,tb_category.category_name FROM   tb_category");
            foreach(DataRow dr in dtFather.Rows)
            {
                 
                TreeNode tn = new TreeNode();
                tn.Value = dr["category_id"].ToString();
                tn.Text = dr["category_name"].ToString();
                TreeView1.Nodes.Add(tn);
                DataTable dtChild = exe_Table("server=localhost;user id=root;password=root;database=em",
                    "select type_id,type_name,category_id from tb_type where tb_type.category_id=" + dr["category_id"].ToString());
                foreach (DataRow drChild in dtChild.Rows)
                {
                    TreeNode tnChild = new TreeNode();
                    tnChild.Value = drChild["type_id"].ToString();//节点的Value值，一般为数据库的id值
                    tnChild.Text = drChild["type_name"].ToString();//节点的Text，节点的文本显示
                    tn.ChildNodes.Add(tnChild);
                }
 
            }
        }
    }
 
 
 
          /// <summary>
        /// 取出数据库中数据，生成DataTable
        /// </summary>
        /// <param name="str_Con">数据库连接</param>
        /// <param name="str_Cmd">sql语句</param>
        /// <returns></returns>
        private DataTable exe_Table(string str_Con,string str_Cmd)
        {
            DataSet ds = new DataSet();
            using (MySqlConnection conn = new MySqlConnection(str_Con))
            {
                using (MySqlDataAdapter oda = new MySqlDataAdapter(str_Cmd, conn))
                {
                    conn.Open();
                    oda.Fill(ds);
                }
            }
            return ds.Tables[0];
        }
 
 
}
 
 
三层架构绑定：
Model实体类：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
 
namespace Model
{
    public class PNode
    {
        public int id { get; set; }
        public string name { get; set; }
        public string intro { get; set; }
    }
}
 
 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
 
namespace Model
{
    public class Node
    {
        public int id { get; set; }
        public string name { get; set; }
        public int pid { get; set; }
        public string intro { get; set; }
    }
}
 
DAL：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using MySql.Data.MySqlClient;
using System.Data;
using Model;
namespace DAL
{
    public class ListTreeNode
    {
        public static List<PNode> GetPNode()
        {
            string strSql = "select distinct category_id,category_name ,intro from tb_category";
            List<PNode> list = new List<PNode>();
            using (MySqlConnection cn = new MySqlConnection(StrCon.Conn))
            {
                cn.Open();
                MySqlDataAdapter sda = new MySqlDataAdapter(strSql, cn);
                DataSet ds = new DataSet();
                sda.Fill(ds);
                foreach (DataRow dr in ds.Tables[0].Rows)
                {
                    PNode pnode = new PNode();
                    pnode.id = (int)dr["category_id"];
                    pnode.name = dr["category_name"].ToString();
                    pnode.intro = dr["intro"].ToString();
                    list.Add(pnode);
                }
                return list;
            }
        }
 
        public static List<Node> GetNode(int pnode_id)
        {
            string strSql ="select type_id,type_name,tb_type.intro,category_id from tb_type where tb_type.category_id=" + pnode_id;
            List<Node> list = new List<Node>();
            using (MySqlConnection cn = new MySqlConnection(StrCon.Conn))
            {
                cn.Open();
                MySqlDataAdapter sda = new MySqlDataAdapter(strSql, cn);
                DataSet ds = new DataSet();
                sda.Fill(ds);
                foreach (DataRow dr in ds.Tables[0].Rows)
                {
                    Node node = new Node();
                    node.id = (int)dr["type_id"];
                    node.name = dr["type_name"].ToString();
                    node.intro = dr["intro"].ToString();
                    list.Add(node);
                }
                return list;
            }
        }
    }
}
 
BLL:
 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Web;
using System.Web.UI.WebControls;
using DAL;
using Model;
 
namespace BLL
{
    public class VarityManage
    {
        //获得根结点信息
        public static List<PNode> GetPNode()
        {
            return DAL.ListTreeNode.GetPNode(); 
 
        }
        //获得叶结点信息
        public static List<Node> GetNode(int pnode_id)
        {
            return DAL.ListTreeNode.GetNode(pnode_id);
        }
 
    }
}
 
UI:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using BLL;
using Model;
 
namespace E_mall_background_system.Management
{
    public partial class main : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                BindTreeView();
                BindddlSelectPNode1();
            }
        }
 
        //TreeView的绑定
        public void BindTreeView()
        {
            TreeView1.Nodes.Clear();
            int rootId = 0;
            string rootName = "所有商品种类";
            TreeNode root = CreateTreeNode(rootId, rootName);
            TreeView1.Nodes.Add(root);
            List<PNode> pnodes = VarityManage.GetPNode();
            foreach (PNode pnode in pnodes)
            {
                int nodeId = (int)pnode.id;
                string nodeName = pnode.name.ToString();
                TreeNode treeNode = this.CreateTreeNode(nodeId, nodeName);
                root.ChildNodes.Add(treeNode);
                List<Node> nodes = VarityManage.GetNode(nodeId);
                foreach (Node node in nodes)
                {
                    int childNodeId =(int) node.id;
                    string childNodeName = node.name.ToString();
                    TreeNode childTreeNode = this.CreateTreeNode(childNodeId, childNodeName);
                    treeNode.ChildNodes.Add(childTreeNode);
                }
                 
            }
        }
 
        public TreeNode CreateTreeNode(int id, string name)
        {
            TreeNode tn = new TreeNode();
            tn.Value = id.ToString();
            tn.Text = name;
            return tn;
        }
 
    }
}