C#高级：Winform桌面开发中TreeView的基础例子

一、方案一：免递归使用树

namespace WinFormsApp1
{public partial class Form1 : Form{public Form1(){InitializeComponent();}/// <summary>/// 自定义树实体/// </summary>public class WinFormTree{/// <summary>/// 标签名称/// </summary>public string Name { get; set; }/// <summary>/// 本节点ID（根节点Pid=0)/// </summary>public int Id { get; set; }/// <summary>/// 父节点ID/// </summary>public int Pid { get; set; }}//点击触发自定义弹窗输入private async void button1_Click(object sender, EventArgs e){// 假设这是数据源List<WinFormTree> data = new List<WinFormTree>{new WinFormTree { Id = 1, Name = "爷爷", Pid = 0 },new WinFormTree { Id = 2, Name = "父亲", Pid = 1 },new WinFormTree { Id = 3, Name = "儿子", Pid = 2 },new WinFormTree { Id = 4, Name = "女儿", Pid = 2 } // 假设加个子节点};// 调用方法来构建树BuildTree(treeView1,data);}/// <summary>/// 构建树/// </summary>/// <param name="data"></param>private void BuildTree(TreeView treeView,List<WinFormTree> data){//清空树treeView.Nodes.Clear();// 使用字典存储 id -> TreeNode 的映射Dictionary<int, TreeNode> nodeDict = new Dictionary<int, TreeNode>();// 根节点TreeNode rootNode = null;// 遍历所有数据，构建树foreach (var item in data){TreeNode node = new TreeNode(item.Name);// 存储当前节点nodeDict.Add(item.Id, node);// 如果是根节点，保存根节点if (item.Pid == 0){rootNode = node;}else{// 找到父节点并将当前节点添加到父节点下if (nodeDict.ContainsKey(item.Pid)){nodeDict[item.Pid].Nodes.Add(node);}}}// 将树根节点添加到 TreeView 中if (rootNode != null){treeView.Nodes.Add(rootNode);}}/// <summary>/// 树节点选中事件（双击进入该方法）/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void treeView1_AfterSelect(object sender, TreeViewEventArgs e){// 获取选中的节点的文本内容string selectedNodeText = e.Node.Text;// 将选中的节点文本设置到Label控件label1.Text = "选中的标签是: " + selectedNodeText;}}
}

二、方案二：递归求树

namespace WinFormsApp1
{public partial class Form1 : Form{public Form1(){InitializeComponent();}/// <summary>/// 自定义树实体/// </summary>public class WinFormTree{/// <summary>/// 标签名称/// </summary>public string Name { get; set; }/// <summary>/// 本节点ID（根节点Pid=0)/// </summary>public int Id { get; set; }/// <summary>/// 父节点ID/// </summary>public int Pid { get; set; }}//点击触发自定义弹窗输入private async void button1_Click(object sender, EventArgs e){// 假设这是数据源List<WinFormTree> data = new List<WinFormTree>{new WinFormTree { Id = 1, Name = "爷爷", Pid = 0 },new WinFormTree { Id = 2, Name = "父亲", Pid = 1 },new WinFormTree { Id = 3, Name = "儿子", Pid = 2 },new WinFormTree { Id = 4, Name = "女儿", Pid = 2 } // 假设加个子节点};// 调用方法来构建树BuildTree(treeView1,data);}/// <summary>/// 构建树/// </summary>/// <param name="data"></param>private void BuildTree(TreeView treeView,List<WinFormTree> data){//清空树treeView.Nodes.Clear();// 根节点TreeNode rootNode = GetTreeByData(data);// 将树根节点添加到 TreeView 中if (rootNode != null){treeView.Nodes.Add(rootNode.FirstNode);}}private TreeNode GetTreeByData(List<WinFormTree> data, int parentId = 0){// 使用 LINQ 获取所有子节点var nodes = data.Where(x => x.Pid == parentId).Select(item =>{var node = new TreeNode(item.Name);node.Nodes.AddRange(GetTreeByData(data, item.Id).Nodes.Cast<TreeNode>().ToArray()); // 递归添加子节点return node;}).ToList();// 创建一个父节点并将子节点添加进去var parentNode = new TreeNode();parentNode.Nodes.AddRange(nodes.ToArray());  // 添加所有子节点return parentNode;}/// <summary>/// 树节点选中事件（双击进入该方法）/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void treeView1_AfterSelect(object sender, TreeViewEventArgs e){// 获取选中的节点的文本内容string selectedNodeText = e.Node.Text;// 将选中的节点文本设置到Label控件label1.Text = "选中的标签是: " + selectedNodeText;}}
}

三、效果图