C# 中的动态树 [关闭]

Question

任何人都可以帮助我在 c# 中执行此操作并允许用户添加或删除节点，或者是否有任何库。 谢谢

Answer 1

您可以创建一个继承面板的类，然后创建一个不可见的 TreeView（用于存储数据）并覆盖 OnPaint。下面是一些示例代码，它会生成一些带有文本的圆圈，但它们之间没有线条。此外，绘制子节点的部分不会生成超过四行，但可以修改以生成更多。

代码：

using System;
using System.Linq;
using System.Drawing;
using System.Windows.Forms;
using System.Collections.Generic;

public class BinaryTreeView : Panel
{   
    public BinaryTreeView()
    {
        this.Location = new Point(2, 2);
        this.Size = new Size(500, 400);
        this.BackColor = Color.White;
        this.Font = new Font(this.Font.Name, 21f, FontStyle.Bold);
    }

    public void AddParent(string nodeName)
    {
        binaryTreeViewData.Nodes.Add(new TreeNode() { Name = nodeName });
        this.Refresh();
    }

    public void Add(string nodeName, string parentNode)
    {
        try { binaryTreeViewData.Nodes.Find(parentNode, true)[0].Nodes.Add(new TreeNode() { Name = nodeName }); } catch { }
        this.Refresh();
    }

    public void Remove(string nodeName)
    {
        // find and remove code.
        this.Refresh();
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        base.OnPaint(e);

        List<TreeNode> childNodes = new List<TreeNode>();

        for (int i = (binaryTreeViewData.Nodes.Count - 1); i > -1; i--)
        {
            Point nodePos = new Point(((this.Width - (55 * binaryTreeViewData.Nodes.Count)) / 2) + (i * 55), 5);
            e.Graphics.DrawEllipse(new Pen(new SolidBrush(Color.Black), 3), new Rectangle(nodePos.X, nodePos.Y, 50, 50));
            e.Graphics.DrawString(binaryTreeViewData.Nodes[i].Name, this.Font, new SolidBrush(this.ForeColor), nodePos.X + 11, nodePos.Y + 9);

            foreach (TreeNode childNode in binaryTreeViewData.Nodes[i].Nodes)
            {
                childNodes.Add(childNode);
            }
        }

        // Child node drawing part.
        List<TreeNode> childNodes2 = new List<TreeNode>();
        childNodes.Reverse();

        for (int i = (childNodes.Count - 1); i > -1; i--)
        {
            Point nodePos = new Point(((this.Width - (55 * childNodes.Count)) / 2) + (i * 55), 65);
            e.Graphics.DrawEllipse(new Pen(new SolidBrush(Color.Black), 3), new Rectangle(nodePos.X, nodePos.Y, 50, 50));
            e.Graphics.DrawString(childNodes[i].Name, this.Font, new SolidBrush(this.ForeColor), nodePos.X + 11, nodePos.Y + 9);

            foreach (TreeNode childNode in childNodes[i].Nodes)
            {
                childNodes2.Add(childNode);
            }
        }

        List<TreeNode> childNodes3 = new List<TreeNode>();
        childNodes2.Reverse();

        for (int i = (childNodes2.Count - 1); i > -1; i--)
        {
            Point nodePos = new Point(((this.Width - (55 * childNodes2.Count)) / 2) + (i * 55), 125);
            e.Graphics.DrawEllipse(new Pen(new SolidBrush(Color.Black), 3), new Rectangle(nodePos.X, nodePos.Y, 50, 50));
            e.Graphics.DrawString(childNodes2[i].Name, this.Font, new SolidBrush(this.ForeColor), nodePos.X + 11, nodePos.Y + 9);

            foreach (TreeNode childNode in childNodes2[i].Nodes)
            {
                childNodes3.Add(childNode);
            }
        }

        childNodes3.Reverse();

        for (int i = (childNodes3.Count - 1); i > -1; i--)
        {
            Point nodePos = new Point(((this.Width - (55 * childNodes3.Count)) / 2) + (i * 55), 185);
            e.Graphics.DrawEllipse(new Pen(new SolidBrush(Color.Black), 3), new Rectangle(nodePos.X, nodePos.Y, 50, 50));
            e.Graphics.DrawString(childNodes3[i].Name, this.Font, new SolidBrush(this.ForeColor), nodePos.X + 11, nodePos.Y + 9);
        }
    }

    private TreeView binaryTreeViewData = new TreeView();
}

用法：

BinaryTreeView BinaryTreeViewExample = new BinaryTreeView();
BinaryTreeViewExample.AddParent("A");

BinaryTreeViewExample.Add("D", "A");
BinaryTreeViewExample.Add("J", "D");
BinaryTreeViewExample.Add("O", "J");
BinaryTreeViewExample.Add("N", "J");
BinaryTreeViewExample.Add("I", "D");
BinaryTreeViewExample.Add("H", "D");

BinaryTreeViewExample.Add("C", "A");
BinaryTreeViewExample.Add("G", "C");
BinaryTreeViewExample.Add("M", "G");
BinaryTreeViewExample.Add("L", "G");

BinaryTreeViewExample.Add("B", "A");
BinaryTreeViewExample.Add("F", "B");
BinaryTreeViewExample.Add("E", "B");
BinaryTreeViewExample.Add("K", "E");

...Controls.Add(BinaryTreeViewExample);

结果：

注意：你必须反向添加元素，因为绘图功能是反向绘制节点。