C# GDI+绘制雷达图的实例
这篇文章主要介绍了C# 使用GDI绘制雷达图，本文通过一段实例代码给大家介绍的非常详细，具有一定的参考借鉴价值。
项目要用C#实现画一个雷达图，实现效果如下图：
代码如下：
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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(); } } |
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
总结
以上所述是给大家介绍的C# 使用GDI绘制雷达图的实例，希望对大家有所帮助。
