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using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;

using System.Text;
//using System.Text.StringBuilder;

public partial class Tree1 : System.Web.UI.Page
{

protected System.Data.SqlClient.SqlConnection SqlConnection1;
    protected System.Data.SqlClient.SqlDataAdapter SqlDataAdapter1;
    protected System.Data.DataSet DataSet1;
    protected System.Data.DataSet DataSet2;
    string Str_sql = "";
    static string Str_selected = "";  // 选中的值
   
   
    protected void Page_Load(object sender, EventArgs e)
    {
        AddTree(0, null);
    }

private void AddTree(int Pid, TreeNode PNode)
    {
        //string sqlStr = "SELECT Item_id,Item_name,Parent_ID FROM Para_item";
        //DataTable dt = YSqlHelper.ExecuteQuery(sqlStr, CommandType.Text);

if (!IsPostBack)
        {

P_ht.H_data P_data = new P_ht.H_data();
            P_data.sql_text1 = "SELECT Item_id,Item_name,Parent_ID FROM Para_item";
            Str_sql = P_data.sql_text1;
            P_data.select_tables();
            DataSet1 = P_data.DataSet8;
            DataTable dt = DataSet1.Tables[0];

if (dt.Rows.Count > 0)
            {
                DataView dv = new DataView(dt);
                //过滤ParentID,得到当前的所有子节点 ParentID为父节点ID
                dv.RowFilter = "[Parent_ID] = " + Pid;
                //循环递归
                foreach (DataRowView Row in dv)
                {
                    //声明节点
                    TreeNode Node = new TreeNode();
                    //绑定超级链接
                    // Node.NavigateUrl = String.Format("javascript:show(‘{0}‘)", Row["Item_Name"].ToString());
                    //开始递归
                    if (PNode == null)
                    {
                        //添加根节点
                        Node.Text = Row["Item_Name"].ToString();
                        this.TreeView1.Nodes.Add(Node);
                        Node.Expanded = true; //节点状态展开
                        AddTree(Int32.Parse(Row["Item_ID"].ToString()), Node);    //再次递归
                    }
                    else
                    {
                        //添加当前节点的子节点
                        Node.Text = Row["Item_Name"].ToString();
                        PNode.ChildNodes.Add(Node);
                        Node.Expanded = true; //节点状态展开
                        AddTree(Int32.Parse(Row["Item_ID"].ToString()), Node);     //再次递归
                    }
                }
            }
        }
    }