C# 使用GDI绘制雷达图的实例

public static class RadarDemo  {    static float mW = 1200;    static float mH = 1200;    static Dictionary<string, float> mData = new Dictionary<string, float>    {        //{ "速度",77},        { "力量", 72},        { "防守", 110},        { "射门", 50},        { "传球", 80},        { "耐力", 60 }    };//维度数据    static float mCount = mData.Count; //边数    static float mCenter = mW * 0.5f; //中心点    static float mRadius = mCenter - 100; //半径(减去的值用于给绘制的文本留空间)    static double mAngle = (Math.PI * 2) / mCount; //角度    static Graphics graphics = null;    static int mPointRadius = 5; // 各个维度分值圆点的半径      static int textFontSize = 18;  //顶点文字大小 px    const string textFontFamily = "Microsoft Yahei"; //顶点字体    static Color lineColor = Color.Green;    static Color fillColor = Color.FromArgb(128, 255, 0, 0);    static Color fontColor = Color.Black;    public static void Show()    {      Bitmap img = new Bitmap((int)mW, (int)mH);       graphics = Graphics.FromImage(img);       graphics.Clear(Color.White);      img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/0.png", ImageFormat.Png);      DrawPolygon(graphics);      img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/1.png", ImageFormat.Png);      DrawLines(graphics);      img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/2.png", ImageFormat.Png);      DrawText(graphics);      img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/3.png", ImageFormat.Png);      DrawRegion(graphics);      img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/4.png", ImageFormat.Png);      DrawCircle(graphics);      img.Save($"{AppDomain.CurrentDomain.BaseDirectory}radar/5.png", ImageFormat.Png);      img.Dispose();      graphics.Dispose();    }    // 绘制多边形边    private static void DrawPolygon(Graphics ctx)    {      var r = mRadius / mCount; //单位半径      Pen pen = new Pen(lineColor);      //画6个圈      for (var i = 0; i < mCount; i++)      {        var points = new List<PointF>();        var currR = r * (i + 1); //当前半径        //画6条边        for (var j = 0; j < mCount; j++)        {          var x = (float)(mCenter + currR * Math.Cos(mAngle * j));          var y = (float)(mCenter + currR * Math.Sin(mAngle * j));          points.Add(new PointF { X = x, Y = y });        }        ctx.DrawPolygon(pen, points.ToArray());        //break;      }      ctx.Save();    }    //顶点连线    private static void DrawLines(Graphics ctx)    {      for (var i = 0; i < mCount; i++)      {        var x = (float)(mCenter + mRadius * Math.Cos(mAngle * i));        var y = (float)(mCenter + mRadius * Math.Sin(mAngle * i));        ctx.DrawLine(new Pen(lineColor), new PointF { X = mCenter, Y = mCenter }, new PointF { X = x, Y = y });        //break;      }      ctx.Save();    }    //绘制文本    private static void DrawText(Graphics ctx)    {      var fontSize = textFontSize;//mCenter / 12;      Font font = new Font(textFontFamily, fontSize, FontStyle.Regular);      int i = 0;      foreach (var item in mData)      {        var x = (float)(mCenter + mRadius * Math.Cos(mAngle * i));        var y = (float)(mCenter + mRadius * Math.Sin(mAngle * i) - fontSize);        if (mAngle * i > 0 && mAngle * i <= Math.PI / 2)        {          ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x - ctx.MeasureString(item.Key, font).Width * 0.5f, y + fontSize/* y + fontSize*/);        }        else if (mAngle * i > Math.PI / 2 && mAngle * i <= Math.PI)        {          ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x - ctx.MeasureString(item.Key, font).Width, y /*y + fontSize*/);        }        else if (mAngle * i > Math.PI && mAngle * i <= Math.PI * 3 / 2)        {          ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x - ctx.MeasureString(item.Key, font).Width, y);        }        else if (mAngle * i > Math.PI * 3 / 2)        {          ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x - ctx.MeasureString(item.Key, font).Width * 0.5f, y - fontSize * 0.5f);        }        else        {          ctx.DrawString(item.Key, font, new SolidBrush(fontColor), x, y /* y + fontSize*/);        }        i++;      }      ctx.Save();    }    //绘制数据区域    private static void DrawRegion(Graphics ctx)    {      int i = 0;      List<PointF> points = new List<PointF>();      foreach (var item in mData)      {        var x = (float)(mCenter + mRadius * Math.Cos(mAngle * i) * item.Value / 100);        var y = (float)(mCenter + mRadius * Math.Sin(mAngle * i) * item.Value / 100);        points.Add(new PointF { X = x, Y = y });        //ctx.DrawArc(new Pen(lineColor), x, y, r, r, 0, (float)Math.PI * 2);         i++;      }      //GraphicsPath path = new GraphicsPath();      //path.AddLines(points.ToArray());      ctx.FillPolygon(new SolidBrush(fillColor), points.ToArray());      ctx.Save();    }    //画点    private static void DrawCircle(Graphics ctx)    {      //var r = mCenter / 18;      var r = mPointRadius;      int i = 0;      foreach (var item in mData)      {        var x = (float)(mCenter + mRadius * Math.Cos(mAngle * i) * item.Value / 100);        var y = (float)(mCenter + mRadius * Math.Sin(mAngle * i) * item.Value / 100);        ctx.FillPie(new SolidBrush(fillColor), x - r, y - r, r * 2, r * 2, 0, 360);        //ctx.DrawArc(new Pen(lineColor), x, y, r, r, 0, (float)Math.PI * 2);         i++;      }      ctx.Save();    }  }