treeview控件中的节点怎么保存
treeview控件中的节点怎么保存,每次保存完之后再打开程序就发现不见了,请问有没有具体代码,详细点,谢谢.求,急 --------------------编程问答-------------------- treeview 只是显示控件 不会给你存数据 你新建的节点必须持久化数据库或本地文件中等 你下次再打开时又去读数据库或文件 再把节点加载到树上！ --------------------编程问答--------------------
你好,我可以怎么去做,可以有代码贴出来吗?我是新手啦,谢谢 --------------------编程问答-------------------- 逐级逐节点的保存，每一级要有个表示，比如缩进 --------------------编程问答-------------------- 可以保存成xml文件，那样读取时，节点层次关系好控制 --------------------编程问答--------------------
只能说,我没有办法做啊,求代码啊,谢谢 --------------------编程问答-------------------- 最简单的 自己添加几个节点 应该不会不见吧 动态的就是代码生成节点 然后绑定到数据库 --------------------编程问答-------------------- 一棵树的全部源码：
请参考：
http://topic.csdn.net/u/20110224/15/b8f65ab8-bc09-400c-a82e-1534f657b292.html
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace testcheckbox
{
public partial class treeview : Form
{
public treeview()
{
InitializeComponent();
}
//定义数据集，将树信息放入DataTable中
DataSet ds = new DataSet();
//树节点是否完全展开
private bool isexpand=false;
//选中的节点的id
private int nodeid = -1;
//数据库连接字符串
private string connstr="data source=127.1;initial catalog=test; user id=sa; password=sa;";
private void treeview_Load(object sender, EventArgs e)
{
DateTime s = DateTime.Now;
tv_bind();
toolStripStatusLabel1.Text ="构造树耗时："+DateTime.Now.Subtract(s).TotalMilliseconds+"毫秒";
}
//将数据库中的分类信息放入数据表中
private void tv_bind()
{
try
{
//从数据库中读取分类信息至DataSet
using (SqlConnection conn = new SqlConnection(connstr))
{
using (SqlDataAdapter da = new SqlDataAdapter("select * from bumen", conn))
{
da.Fill(ds,"bumen");
}
}
//如果数据库中有信息那么构造树，否则提示无接点
if (ds.Tables["bumen"].Rows.Count > 0)
{
//清除树节点，从根添加树
treeView1.Nodes.Clear();
Add_tree(0,(TreeNode)null);
}
else
{
treeView1.Nodes.Clear();
TreeNode node = new TreeNode();
node.Text = "暂无任何分类信息";
treeView1.Nodes.Add(node);
}
}
catch
{
treeView1.Nodes.Clear();
TreeNode node = new TreeNode();
node.Text = "暂无任何分类信息：请检查数据库连接是否正常";
treeView1.Nodes.Add(node);
}
}
//递归树
private void Add_tree(int pid,TreeNode pnode)
{
DataRow[] dr = ds.Tables["bumen"].Select("pid="+pid);
foreach (DataRow row in dr)
{
TreeNode node = new TreeNode();
if (pnode == null)
{
node.Text = row["bumen"].ToString();
node.Tag = row["id"].ToString();
treeView1.Nodes.Add(node);
Add_tree(int.Parse(row["id"].ToString()),node);
}
else
{
node.Text = row["bumen"].ToString();
node.Tag = row["id"].ToString();
pnode.Nodes.Add(node);
Add_tree(int.Parse(row["id"].ToString()),node);
}
}
}
private void toolStripLabel1_Click(object sender, EventArgs e)
{
if (isexpand)
{
isexpand = false;
treeView1.CollapseAll();
}
else
{
isexpand = true;
treeView1.ExpandAll();
}
}
private void treeView1_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e)
{
if (e.Button == MouseButtons.Right)
{
//选中右键点击的节点
treeView1.SelectedNode = e.Node;
//显示右键菜单
contextMenuStrip1.Visible = true;
//设置右键菜单的位置
contextMenuStrip1.Left = MousePosition.X;
contextMenuStrip1.Top = MousePosition.Y;
}
else
{
//点击其他节点时，取消正在编辑状态的节点
textBox1.Text = "";
groupBox1.Enabled = false;
//显示当前选择的节点的信息
richTextBox1.Text = "名称："+e.Node.Text+"\n节点属性："+e.Node.Tag;
//根据点击的节点到yuangong表提取对应的员工，然后在listview中显示
listView1.Clear();
using (SqlConnection conn = new SqlConnection(connstr))
{
conn.Open();
using (SqlCommand cmd = new SqlCommand("select yuangong from yuangong where bid=" + e.Node.Tag, conn))
{
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
listView1.Items.Add(dr[0].ToString());
}
dr.Close();
}
}
}
}
private void 编辑节点ToolStripMenuItem_Click(object sender, EventArgs e)
{
if (int.Parse(treeView1.SelectedNode.Tag.ToString()) >-1)
{
nodeid = int.Parse(treeView1.SelectedNode.Tag.ToString());
groupBox1.Enabled = true;
textBox1.Text = treeView1.SelectedNode.Text;
}
else
{
MessageBox.Show("请选择要编辑的节点");
}
}
private void button1_Click(object sender, EventArgs e)
{
if (nodeid > -1)
{
//检查同级别节点是否有重名
using (SqlConnection conn = new SqlConnection("data source=127.1;initial catalog=test;user id=sa;password=sa;"))
{
conn.Open();
using (SqlCommand cmd = new SqlCommand("select count(id) from bumen where pid=(select pid from bumen where id=" + nodeid + ") and bumen='" + textBox1.Text.Trim() + "' and id<>"+nodeid, conn))
{
int i = int.Parse(cmd.ExecuteScalar().ToString());
if (i > 0)
{
MessageBox.Show("错误！该分类已经存在同名节点");
}
else
{
cmd.CommandText = "update bumen set bumen='"+textBox1.Text.Trim()+"' where id="+nodeid;
int isupdateok = cmd.ExecuteNonQuery();
if (isupdateok == 1)
{
MessageBox.Show("编辑节点信息成功！");
textBox1.Text = "";
groupBox1.Enabled = false;
treeView1.Nodes.Clear();
tv_bind();
treeView1.ExpandAll();
}
else
{
MessageBox.Show("编辑节点信息失败！请重新编辑","错误",MessageBoxButtons.OK,MessageBoxIcon.Error);
}
}
}
}
}
}
}
}
如果想要源码给我留下邮箱地址，我给你发一个 --------------------编程问答-------------------- TreeNode node = new TreeNode("node");
this.treeview1.Nodes.add(node); --------------------编程问答-------------------- 节点的数据要写入到数据源中，然后界面显示的时候再读出来！ --------------------编程问答-------------------- private void tvType_AfterLabelEdit(object sender, NodeLabelEditEventArgs e)
{
if (e.Node.Level == 0 || string.IsNullOrEmpty(e.Label) ||
this.tvManager.FindNameInTable(e.Label))
{
e.CancelEdit = true;
return;
}
this.tvManager.ChangeNodeValue(e.Node.Tag.ToString(), e.Label); // 更改值
}
http://www.360doc.com/content/10/1218/16/4480089_79281385.shtml --------------------编程问答-------------------- --------------------编程问答-------------------- 完善了一下我的树，增加了添加节点功能（没注意以前写的只能编辑不能添加，不好意思啊呵呵）
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.OleDb;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace myTreeView
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
//定义数据集，将树信息放入DataTable中
DataSet ds = new DataSet();
//树节点是否完全展开
private bool isexpand = false;
//选中的节点的id
private int nodeid = -1;
private TreeNode lastnode;
//定义数据库的连接字符串
private string connstr = "Provider=Microsoft.ACE.OLEDB.12.0; Data Source=db.mdb;";
private void Form1_Load(object sender, EventArgs e)
{
tv_bind();
}
private void tv_bind()
{
try
{
//从数据库中读取分类信息至DataSet
//绑定前先清空数据集
ds.Clear();
treeView1.Nodes.Clear();
using (OleDbConnection conn = new OleDbConnection(connstr))
{
using (OleDbDataAdapter da = new OleDbDataAdapter("select * from tree", conn))
{
da.Fill(ds, "tree");
}
}
//如果数据库中有信息那么构造树，否则提示无接点
if (ds.Tables["tree"].Rows.Count > 0)
{
//清除树节点，从根添加树
treeView1.Nodes.Clear();
Add_tree(0, (TreeNode)null);
}
else
{
treeView1.Nodes.Clear();
TreeNode node = new TreeNode();
node.Text = "暂无任何分类信息";
treeView1.Nodes.Add(node);
}
}
catch
{
treeView1.Nodes.Clear();
TreeNode node = new TreeNode();
node.Text = "暂无任何分类信息：请检查数据库连接是否正常";
treeView1.Nodes.Add(node);
}
}
//递归树
private void Add_tree(int pid, TreeNode pnode)
{
DataRow[] dr = ds.Tables["tree"].Select("pid=" + pid);
foreach (DataRow row in dr)
{
TreeNode node = new TreeNode();
if (pnode == null)
{
node.Text = row["nodename"].ToString();
node.Tag = row["id"].ToString();
treeView1.Nodes.Add(node);
Add_tree(int.Parse(row["id"].ToString()), node);
}
else
{
node.Text = row["nodename"].ToString();
node.Tag = row["id"].ToString();
pnode.Nodes.Add(node);
Add_tree(int.Parse(row["id"].ToString()), node);
}
}
}
private void treeView1_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e)
{
//如果在节点上点击的是左键
if (e.Button == MouseButtons.Left)
{
//根据点击的节点到yuangong表提取对应的员工，然后在listview中显示
listView1.Clear();
using (OleDbConnection conn = new OleDbConnection(connstr))
{
conn.Open();
using (OleDbCommand cmd = new OleDbCommand("select products_name from products where tid=" + e.Node.Tag, conn))
{
OleDbDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
listView1.Items.Add(dr[0].ToString());
}
dr.Close();
}
}
}
//如果在节点上点击鼠标右键
else
{
treeView1.SelectedNode = e.Node;
contextMenuStrip1.Visible = true;
contextMenuStrip1.Left = MousePosition.X;
contextMenuStrip1.Top = MousePosition.Y;
}
}
private void 折叠展开树ToolStripMenuItem_Click(object sender, EventArgs e)
{
if (isexpand)
{
isexpand = false;
treeView1.CollapseAll();
}
else
{
isexpand = true;
treeView1.ExpandAll();
}
}
private void 编辑节点ToolStripMenuItem_Click(object sender, EventArgs e)
{
if (int.Parse(treeView1.SelectedNode.Tag.ToString()) > -1)
{
nodeid = int.Parse(treeView1.SelectedNode.Tag.ToString());
lastnode = treeView1.SelectedNode;
groupBox1.Enabled = true;
textBox1.Text = treeView1.SelectedNode.Text;
button1.Text = "编辑";
}
else
{
MessageBox.Show("请选择要编辑的节点");
}
}
private void 添加子节点ToolStripMenuItem_Click(object sender, EventArgs e)
{
if (int.Parse(treeView1.SelectedNode.Tag.ToString()) > -1)
{
nodeid = int.Parse(treeView1.SelectedNode.Tag.ToString());
groupBox1.Enabled = true;
button1.Text = "添加";
}
else
{
MessageBox.Show("请选择要在哪个节点下添加子节点");
}
}
private void button1_Click(object sender, EventArgs e)
{
//判断是编辑节点还是添加节点
if (button1.Text == "编辑"&&textBox1.Text.Trim().Length>0)
{
if (nodeid > -1)
{
//检查同级别节点是否有重名
using (OleDbConnection conn = new OleDbConnection(connstr))
{
conn.Open();
using (OleDbCommand cmd = new OleDbCommand("select count(id) from tree where pid=(select pid from tree where id=" + nodeid + ") and nodename='" + textBox1.Text.Trim() + "' and id<>" + nodeid, conn))
{
int i = int.Parse(cmd.ExecuteScalar().ToString());
if (i > 0)
{
MessageBox.Show("错误！该分类已经存在同名节点");
}
else
{
cmd.CommandText = "update tree set nodename='" + textBox1.Text.Trim() + "' where id=" + nodeid;
int isupdateok = cmd.ExecuteNonQuery();
if (isupdateok == 1)
{
MessageBox.Show("编辑节点信息成功！");
textBox1.Text = "";
groupBox1.Enabled = false;
tv_bind();
}
else
{
MessageBox.Show("编辑节点信息失败！请重新编辑", "错误", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
}
}
}
else if (button1.Text == "添加")
{
if (textBox1.Text.Trim().Length > 0)
{
using (OleDbConnection conn = new OleDbConnection(connstr))
{
conn.Open();
string addsql = "select count(id) From tree where pid=" + nodeid + " and nodename='" + textBox1.Text.Trim()+"'";
using (OleDbCommand addcmd = new OleDbCommand(addsql, conn))
{
int iscanadd = int.Parse(addcmd.ExecuteScalar().ToString());
if (iscanadd > 0)
{
MessageBox.Show("对不起，已存在同名节点");
}
else
{
string intsql = "Insert into tree(pid,nodename) values(" + nodeid + ",'" + textBox1.Text.Trim() + "')";
using (OleDbCommand cmd = new OleDbCommand(intsql, conn))
{
int isaddok = cmd.ExecuteNonQuery();
if (isaddok > 0)
{
MessageBox.Show("添加节点成功！");
tv_bind();
treeView1.ExpandAll();
}
else
{
MessageBox.Show("添加节点失败，请重新尝试。");
}
}
}
}
}
}
else
{
MessageBox.Show("节点名称不能为空！");
}
}
else
{
MessageBox.Show("请从右键菜单选择您要进行的操作");
}
}
}
}
自己测试吧，需要源文件留下邮箱
补充：.NET技术 , C#
