C#使用MindFusion.Diagramming框架绘制流程图(3):加权图的最短路径算法
上一篇流程图示例
C#使用MindFusion.Diagramming框架绘制流程图(2):流程图示例-CSDN博客
这里我们以之前的最短路径算法为例
最短路径算法-CSDN博客
使用MindFusion.Diagramming画出流程图,并按照当前示例图实现最短路径算法
[迪杰斯特拉最短路径算法]
我们使用MindFusion.Diagramming.DiagramItem的属性Weight权重来进行处理
我们设定MindFusion.Diagramming.DiagramLink连接是双向的权重,连接的文本就显示为权重Weight
MindFusion.Diagramming.DiagramNode节点之间的最短路径
如下图:
新建窗体FormDijkstraDiagram,
窗体FormDijkstraDiagram设计器程序如下:
文件:FormDijkstraDiagram.designer.cs
namespace FlowDiagramDemo
{partial class FormDijkstraDiagram{/// <summary>/// Required designer variable./// </summary>private System.ComponentModel.IContainer components = null;/// <summary>/// Clean up any resources being used./// </summary>/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>protected override void Dispose(bool disposing){if (disposing && (components != null)){components.Dispose();}base.Dispose(disposing);}#region Windows Form Designer generated code/// <summary>/// Required method for Designer support - do not modify/// the contents of this method with the code editor./// </summary>private void InitializeComponent(){this.diagramView1 = new MindFusion.Diagramming.WinForms.DiagramView();this.diagram1 = new MindFusion.Diagramming.Diagram();this.btnGetMinRouter = new System.Windows.Forms.Button();this.SuspendLayout();// // diagramView1// this.diagramView1.Diagram = this.diagram1;this.diagramView1.Dock = System.Windows.Forms.DockStyle.Fill;this.diagramView1.LicenseKey = null;this.diagramView1.Location = new System.Drawing.Point(0, 0);this.diagramView1.Name = "diagramView1";this.diagramView1.Size = new System.Drawing.Size(989, 679);this.diagramView1.TabIndex = 3;this.diagramView1.Text = "diagramView1";// // diagram1// this.diagram1.TouchHitDistance = null;// // btnGetMinRouter// this.btnGetMinRouter.Location = new System.Drawing.Point(14, 2);this.btnGetMinRouter.Name = "btnGetMinRouter";this.btnGetMinRouter.Size = new System.Drawing.Size(223, 37);this.btnGetMinRouter.TabIndex = 4;this.btnGetMinRouter.Text = "打印节点A到达其他节点的最短路径";this.btnGetMinRouter.UseVisualStyleBackColor = true;this.btnGetMinRouter.Click += new System.EventHandler(this.btnGetMinRouter_Click);// // FormDijkstraDiagram// this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;this.ClientSize = new System.Drawing.Size(989, 679);this.Controls.Add(this.btnGetMinRouter);this.Controls.Add(this.diagramView1);this.Name = "FormDijkstraDiagram";this.Text = "加权图(Graph)的迪杰斯特拉最短路径算法-斯内科";this.Load += new System.EventHandler(this.FormDijkstraDiagram_Load);this.ResumeLayout(false);}#endregionprivate MindFusion.Diagramming.WinForms.DiagramView diagramView1;private MindFusion.Diagramming.Diagram diagram1;private System.Windows.Forms.Button btnGetMinRouter;}
}窗体FormDijkstraDiagram相关程序如下:
文件:FormDijkstraDiagram.cs
using MindFusion.Diagramming;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;namespace FlowDiagramDemo
{public partial class FormDijkstraDiagram : Form{/// <summary>/// 顶点个数/// </summary>public const int VertexCount = 6;/// <summary>/// 无法直接到达的距离，无限远的距离/// </summary>public const float Infinity = 99999;/// <summary>/// 图的顶点集合，数组的每一个元素代表一个顶点【元组的第一项代表顶点名称，第二项代表是否已被访问】/// </summary>public Tuple<string, bool>[] VertexTuples = new Tuple<string, bool>[VertexCount];/// <summary>/// 表示两点之间的距离。如：/// MatrixDistance[0,1]=88 表示 【索引为0的顶点】 到 【索引为1的顶点】 之间的距离是88/// </summary>public float[,] MatrixDistance = new float[VertexCount, VertexCount];/// <summary>/// 起点到终点的最短距离/// 元组的第一项代表起点名称，第二项代表终点名称，第三项代表最短距离值，第四项代表当前最短距离的上一个顶点索引/// 本文起点名称固定设置为A，获取A到其他任何一个顶点之间的最短距离，以及运行轨迹路线/// </summary>public Tuple<string, string, float, int>[] MinDistanceTuples = new Tuple<string, string, float, int>[VertexCount];int sequence = 0;public FormDijkstraDiagram(){InitializeComponent();diagram1.AllowSelfLoops = false;//不允许自旋链接diagram1.ShowGrid = true;//显示网格diagram1.AllowUnconnectedLinks = false;//不允许用户绘制未连接到任何节点的链接diagram1.NodeCreating += Diagram1_NodeCreating;//不允许创建节点diagram1.LinkCreating += Diagram1_LinkCreating;//不允许创建连接diagram1.NodeDeleting += Diagram1_NodeDeleting;//不允许删除节点diagram1.LinkDeleting += Diagram1_LinkDeleting;//不允许删除连接}private void Diagram1_LinkDeleting(object sender, LinkValidationEventArgs e){e.Cancel = true;}private void Diagram1_NodeDeleting(object sender, NodeValidationEventArgs e){e.Cancel = true;}private void Diagram1_LinkCreating(object sender, LinkValidationEventArgs e){e.Cancel = true;}private void Diagram1_NodeCreating(object sender, NodeValidationEventArgs e){e.Cancel = true;}/// <summary>/// 初始化所有节点/// </summary>private void InitNode(){sequence = 0;//复位序列号char label = 'A';for (int i = 0; i < VertexTuples.Length; i++){VertexTuples[i] = Tuple.Create(((char)(label + i)).ToString(), false);ShapeNode diagramNode = new ShapeNode(diagram1);diagramNode.AllowIncomingLinks = true;diagramNode.AllowOutgoingLinks = true;diagramNode.Text = VertexTuples[i].Item1;diagramNode.ToolTip = VertexTuples[i].Item1;diagramNode.Font = new Font("宋体", 14);sequence++;diagramNode.Id = sequence;diagramNode.Tag = i;float x = 100;//i==0时，起点A坐标float y = 10;//i==0时，起点A坐标if (i == 1){x = 40;y = 50;}else if (i == 2){x = 90;y = 70;}else if (i == 3){x = 170;y = 60;}else if (i == 4){x = 70;y = 130;}else if (i == 5){x = 150;y = 155;}diagramNode.Bounds = new RectangleF(x, y, 15, 15);diagramNode.Shape = Shapes.Ellipse;//形状：圆diagram1.Nodes.Add(diagramNode); }}/// <summary>/// 添加一条无向边【认为距离是无向的 即A→B，同时B→A】/// 对图来说，就是增加两条连线←→【正向连线 与 反向连线】/// </summary>/// <param name="startIndex">起始索引</param>/// <param name="endIndex">到达索引</param>/// <param name="distance">两点之间的距离</param>private void AddLink(int startIndex, int endIndex, float distance){MatrixDistance[startIndex, endIndex] = distance;//如果距离是有方向的，则去掉下面一行代码MatrixDistance[endIndex, startIndex] = distance;DiagramLink diagramLink = new DiagramLink(diagram1, diagram1.Nodes[startIndex], diagram1.Nodes[endIndex]);diagramLink.Weight = distance;//设置连接的权重diagramLink.Font = new Font("宋体", 14);diagramLink.Text = distance.ToString();if (diagram1.Links.Any(x => x.Origin == diagram1.Nodes[endIndex] && x.Destination == diagram1.Nodes[startIndex])){//如果链接是双向的即←→，则设置文本为空diagramLink.Text = "";}sequence++;diagramLink.Id = sequence;diagramLink.Tag = $"【{diagram1.Nodes[startIndex].Text}】->【{diagram1.Nodes[endIndex].Text}】，权重Weight为【{distance}】";diagram1.Links.Add(diagramLink);//增加反向连线，权重Weight与正向连线一致DiagramLink reverseLink = new DiagramLink(diagram1, diagram1.Nodes[endIndex], diagram1.Nodes[startIndex]);reverseLink.Weight = distance;//设置连接的权重reverseLink.Font = new Font("宋体", 14);reverseLink.Text = distance.ToString();if (diagram1.Links.Any(x => x.Origin == diagram1.Nodes[startIndex] && x.Destination == diagram1.Nodes[endIndex])){//如果链接是双向的即←→，则设置文本为空reverseLink.Text = "";}sequence++;reverseLink.Id = sequence;reverseLink.Tag = $"【{diagram1.Nodes[startIndex].Text}】->【{diagram1.Nodes[startIndex].Text}】，权重Weight为【{distance}】";diagram1.Links.Add(reverseLink);}/// <summary>/// 初始化【权重图】或【距离图】：/// 一、初始化所有顶点，并标记所有顶点都是未访问的/// 二、初始化任意两点的距离都是无穷大的/// 三、图的实际距离【两点之间可以直接连接的部分，也就是 直接连接的顶点之间的距离 覆盖原来的默认值无穷大】/// </summary>public void InitGraph(){InitNode();//初始化最短距离为无穷大，所有矩阵距离都为无穷大for (int i = 0; i < VertexCount; i++){for (int j = 0; j < VertexCount; j++){MatrixDistance[i, j] = Infinity;}}#region 添加边Edge：图的连线部分//AB AC ADAddLink(0, 1, 5);AddLink(0, 2, 3);AddLink(0, 3, 19);//BC BEAddLink(1, 2, 10);AddLink(1, 4, 8);//CD CE CFAddLink(2, 3, 14);AddLink(2, 4, 12);AddLink(2, 5, 9);//DE DFAddLink(3, 4, 5);AddLink(3, 5, 4);//EFAddLink(4, 5, 4);#endregion#region 默认最短距离为无穷大for (int i = 0; i < VertexCount; i++){MinDistanceTuples[i] = Tuple.Create(VertexTuples[0].Item1, VertexTuples[i].Item1, Infinity, 0);}#endregion}/// <summary>/// 设置第一个顶点A到其他顶点的距离是直连的/// ①如果当前顶点A到其他顶点的距离小于Infinity，就以当前距离作为初始最小的距离/// ②找出未访问的顶点中，距离最小的顶点的顶点，然后标记顶点为已访问的/// ③如果当前节点未访问，并且 最短距离+【最短距离的顶点可到达的顶点的距离之和】，那么就设置当前路径为最小距离 需要一个双重循环/// </summary>public void GetRouterPath(){int startIndex = 0;//将第一个顶点更新为已访问VertexTuples[startIndex] = Tuple.Create(VertexTuples[startIndex].Item1, true);for (int i = 0; i < VertexCount; i++){if (MatrixDistance[startIndex, i] < MinDistanceTuples[i].Item3){//因元组无法为第三项赋值，只能重建元组了MinDistanceTuples[i] = Tuple.Create(MinDistanceTuples[i].Item1, MinDistanceTuples[i].Item2, MatrixDistance[startIndex, i], startIndex);}}for (int cnt = 1; cnt < VertexCount; cnt++){//找出最小的距离对应的顶点索引,并将当前顶点设置为已访问int minIndex = FindMinDistanceIndex();float minDist = MinDistanceTuples[minIndex].Item3;//设置为已访问该顶点VertexTuples[minIndex] = Tuple.Create(VertexTuples[minIndex].Item1, true);for (int i = 0; i < VertexCount; i++){//如果当前节点未访问，并且 最短距离+【最短距离的顶点可到达的顶点的距离之和】 还要比原来的还要短，就用新的最短距离赋值if (!VertexTuples[i].Item2 && minDist + MatrixDistance[minIndex, i] < MinDistanceTuples[i].Item3){//记录上一个最短距离顶点的索引MinDistanceTuples[i] = Tuple.Create(MinDistanceTuples[i].Item1, MinDistanceTuples[i].Item2, minDist + MatrixDistance[minIndex, i], minIndex);}}}}/// <summary>/// 显示最短路径的详细信息/// </summary>/// <param name="vertexIndex"></param>/// <returns></returns>public string DisplayDescription(int vertexIndex){return $"最短路径长度：{VertexTuples[0].Item1}->{VertexTuples[vertexIndex].Item1}，最短距离{MinDistanceTuples[vertexIndex].Item3},上一个顶点索引:{MinDistanceTuples[vertexIndex].Item4}.\n" +$" 完整路由：{GetSerialPath(vertexIndex)}";}/// <summary>/// 获取连续节点路线/// </summary>/// <param name="parentIndex"></param>/// <returns></returns>private string GetSerialPath(int parentIndex){Stack<string> stack = new Stack<string>();stack.Push(VertexTuples[parentIndex].Item1);while (parentIndex != 0){parentIndex = MinDistanceTuples[parentIndex].Item4;stack.Push(VertexTuples[parentIndex].Item1);}return string.Join("->", stack);}/// <summary>/// 找出最小的距离对应的顶点索引/// </summary>/// <returns></returns>private int FindMinDistanceIndex(){//找出未访问的顶点中，距离最小的顶点的起点索引int minIndex = -1;//最小距离所在的索引float minDist = Infinity;//最小距离for (int i = 0; i < VertexCount; i++){if (!VertexTuples[i].Item2 && MinDistanceTuples[i].Item3 < minDist){minIndex = i;minDist = MinDistanceTuples[i].Item3;}}return minIndex;}private void FormDijkstraDiagram_Load(object sender, EventArgs e){InitGraph();}private async void btnGetMinRouter_Click(object sender, EventArgs e){await Task.Run(() => {Stopwatch stopwatch = new Stopwatch();stopwatch.Start();//这里最短路径算法GetRouterPath();List<string> pathRouterList = new List<string>();for (int vertexIndex = 0; vertexIndex < VertexCount; vertexIndex++){pathRouterList.Add(DisplayDescription(vertexIndex));}stopwatch.Stop();MessageBox.Show($"获取最短路径耗时：【{stopwatch.Elapsed.TotalMilliseconds}】ms", "运行耗时(ms)");MessageBox.Show($"{string.Join("\n\n", pathRouterList)}");});}}
}
运行如图:
