最近项目要用C#实现画一个雷达图，搜了搜网上竟然找不到C#画雷达图的解决方案，那么自己实现一个吧
实现效果如下图：
代码如下：
1 public static class RadarDemo
2 {
3 static float mW = 1200;
4 static float mH = 1200;
5 static Dictionary<string, float> mData = new Dictionary<string, float>
6 {
7 //{ "速度",77},
8 { "力量", 72},
9 { "防守", 110},
10 { "射门", 50},
11 { "传球", 80},
12 { "耐力", 60 }
13 };//维度数据
14 static float mCount = mData.Count; //边数
15 static float mCenter = mW * 0.5f; //中心点
16 static float mRadius = mCenter - 100; //半径(减去的值用于给绘制的文本留空间)
17 static double mAngle = (Math.PI * 2) / mCount; //角度
18 static Graphics graphics = null;
19 static int mPointRadius = 5; // 各个维度分值圆点的半径
20 static int textFontSize = 18; //顶点文字大小 px
21 const string textFontFamily = "Microsoft Yahei"; //顶点字体
22 static Color lineColor = Color.Green;
23 static Color fillColor = Color.FromArgb(128, 255, 0, 0);
24 static Color fontColor = Color.Black;
25
26 public static void Show()
27 {
28 Bitmap img = new Bitmap((int)mW, (int)mH);
29 graphics = Graphics.FromImage(img);
30 graphics.Clear(Color.White);
31 img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/0.png", ImageFormat.Png);
32 DrawPolygon(graphics);
33 img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/1.png", ImageFormat.Png);
34 DrawLines(graphics);
35 img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/2.png", ImageFormat.Png);
36 DrawText(graphics);
37 img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/3.png", ImageFormat.Png);
38 DrawRegion(graphics);
39 img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/4.png", ImageFormat.Png);
40 DrawCircle(graphics);
41 img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/5.png", ImageFormat.Png);
42 img.Dispose();
43 graphics.Dispose();
44
45 }
46
47
48 // 绘制多边形边
49 private static void DrawPolygon(Graphics ctx)
50 {
51 var r = mRadius / mCount; //单位半径
52 Pen pen = new Pen(lineColor);
53 //画6个圈
54 for (var i = 0; i < mCount; i++)
55 {
56 var points = new List<PointF>();
57 var currR = r * (i + 1); //当前半径
58 //画6条边
59 for (var j = 0; j < mCount; j++)
60 {
61 var x = (float)(mCenter + currR * Math.Cos(mAngle * j));
62 var y = (float)(mCenter + currR * Math.Sin(mAngle * j));
63 points.Add(new PointF { X = x, Y = y });
64 }
65 ctx.DrawPolygon(pen, points.ToArray());
66 //break;
67 }
68
69 ctx.Save();
70 }
71
72 //顶点连线
73 private static void DrawLines(Graphics ctx)
74 {
75 for (var i = 0; i < mCount; i++)
76 {
77 var x = (float)(mCenter + mRadius * Math.Cos(mAngle * i));
78 var y = (float)(mCenter + mRadius * Math.Sin(mAngle * i));
79 ctx.DrawLine(new Pen(lineColor), new PointF { X = mCenter, Y = mCenter }, new PointF { X = x, Y = y });
80 //break;
81 }
82 ctx.Save();
83 }
84
85 //绘制文本
86 private static void DrawText(Graphics ctx)
87 {
88 var fontSize = textFontSize;//mCenter / 12;
89 Font font = new Font(textFontFamily, fontSize, FontStyle.Regular);
90
91 int i = 0;
92 foreach (var item in mData)
93 {
94 var x = (float)(mCenter + mRadius * Math.Cos(mAngle * i));
95 var y = (float)(mCenter + mRadius * Math.Sin(mAngle * i) - fontSize);
96
97 if (mAngle * i > 0 && mAngle * i <= Math.PI / 2)
98 {
99 ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x - ctx.MeasureString(item.Key, font).Width * 0.5f, y + fontSize/* y + fontSize*/);
100 }
101 else if (mAngle * i > Math.PI / 2 && mAngle * i <= Math.PI)
102 {
103 ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x - ctx.MeasureString(item.Key, font).Width, y /*y + fontSize*/);
104 }
105 else if (mAngle * i > Math.PI && mAngle * i <= Math.PI * 3 / 2)
106 {
107 ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x - ctx.MeasureString(item.Key, font).Width, y);
108 }
109 else if (mAngle * i > Math.PI * 3 / 2)
110 {
111 ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x - ctx.MeasureString(item.Key, font).Width * 0.5f, y - fontSize * 0.5f);
112 }
113 else
114 {
115 ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x, y /* y + fontSize*/);
116 }
117 i++;
118 }
119 ctx.Save();
120 }
121
122 //绘制数据区域
123 private static void DrawRegion(Graphics ctx)
124 {
125 int i = 0;
126 List<PointF> points = new List<PointF>();
127 foreach (var item in mData)
128 {
129 var x = (float)(mCenter + mRadius * Math.Cos(mAngle * i) * item.Value / 100);
130 var y = (float)(mCenter + mRadius * Math.Sin(mAngle * i) * item.Value / 100);
131
132 points.Add(new PointF { X = x, Y = y });
133
134 //ctx.DrawArc(new Pen(lineColor), x, y, r, r, 0, (float)Math.PI * 2);
135 i++;
136 }
137
138
139 //GraphicsPath path = new GraphicsPath();
140 //path.AddLines(points.ToArray());
141
142 ctx.FillPolygon(new SolidBrush(fillColor), points.ToArray());
143
144 ctx.Save();
145 }
146
147 //画点
148 private static void DrawCircle(Graphics ctx)
149 {
150 //var r = mCenter / 18;
151 var r = mPointRadius;
152
153 int i = 0;
154 foreach (var item in mData)
155 {
156 var x = (float)(mCenter + mRadius * Math.Cos(mAngle * i) * item.Value / 100);
157 var y = (float)(mCenter + mRadius * Math.Sin(mAngle * i) * item.Value / 100);
158 ctx.FillPie(new SolidBrush(fillColor), x - r, y - r, r * 2, r * 2, 0, 360);
159 //ctx.DrawArc(new Pen(lineColor), x, y, r, r, 0, (float)Math.PI * 2);
160 i++;
161 }
162 ctx.Save();
163 }
164
165 }
把这个类粘贴到你的项目中，执行RadarDemo.Show();就会在你的根目录里生成雷达图了，为了方便理解怎么画出来的，我把画每一个步骤时的图片都保存下来了。可以自行运行查看