部门树形结构,使用Treeview控件显示部门

部门树形结构。设计张部门表用于存储部门编码、名称、上级部门id，使用Treeview控件显示部门树，并实现部门增删改、移动、折叠等功能。特别提示，部门有层级关系，可用donetbar的adtree控件

代码如下

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace 部门树形结构
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            BindTree("0");
        }
        DBHelp s = new DBHelp();
        private void BindTree(string pid)
        {
            string str = "select * from biao where SJ_id=" + int.Parse(pid);
            DataTable ta = s.getTableBySql(str);
            if (ta.Rows.Count > 0)
            {
                for (int i = 0; i < ta.Rows.Count; i++)
                {
                    TreeNode node = new TreeNode();
                    node.Text = ta.Rows[i]["name"].ToString();
                    node.Tag = ta.Rows[i]["id"].ToString();
                    this.treeView1.Nodes.Add(node);
　　　　　　　　　　　 BindNode(node);
                }
            }
        }
        private void BindNode(TreeNode nd)
        {
            string str = "select * from biao where SJ_id="+ Convert.ToString(nd.Tag);
            DataTable ta = s.getTableBySql(str);
            for (int i = 0; i < ta.Rows.Count; i++)
            {
                TreeNode node = new TreeNode();
                node.Text = ta.Rows[i]["name"].ToString();
                node.Tag = ta.Rows[i]["id"].ToString();
                nd.Nodes.Add(node);//重点
                BindNode(node);
            }
        }

        private void treeView1_AfterSelect(object sender, TreeViewEventArgs e)
        {
            if (treeView1.SelectedNode != null)//重点部分
            {
                txt_id.Text= treeView1.SelectedNode.Tag.ToString();//取值
                txt_name.Text= treeView1.SelectedNode.Text;

                string str = "select * from biao where id=" + int.Parse(txt_id.Text);
                DataTable ta = s.getTableBySql(str);
                txt_sj.Text = ta.Rows[0]["SJ_id"].ToString();
            }
        }
        //添加
        private void buttonX1_Click(object sender, EventArgs e)
        {
            string sql_add =string.Format("insert into biao(name,SJ_id) values('{0}',{1})", txt_name.Text,int.Parse(txt_sj.Text));
            if (s.ExecuteIDUBySql(sql_add) > 0)
            {
                MessageBox.Show("添加成功！", "消息");
            }
            else
            {
                MessageBox.Show("添加失败！", "消息");
            }
            treeView1.Nodes.Clear();
            BindTree("0");
        }
    }
}