Winform绘制圆形图

 1         private void Form_Load(object sender, EventArgs e)
 2         {
 3             PictureBox pic = new PictureBox();
 4             pic.Name = "pic1";
 5             pic.Size = new System.Drawing.Size(17, 17);
 6             pic.BackgroundImage = GetRoundPic(Color.Red);
 7             //pic.Paint += DrawPic_Paint;
 8             this.Controls.Add(pic);
 9         }
10         /// <summary>
11         /// 绘制圆形图，并赋值BackgroundImage
12         /// </summary>
13         public Bitmap GetRoundPic(Color color)
14         {
15             Size size = new Size(16, 16);
16             Bitmap bitmap = new Bitmap(size.Width, size.Height);
17             using (Graphics g = Graphics.FromImage(bitmap))
18             {
19                 using (Brush br = new SolidBrush(color))
20                 {
21                     g.SmoothingMode = SmoothingMode.AntiAlias;
22                     g.InterpolationMode = InterpolationMode.HighQualityBicubic;
23                     g.CompositingQuality = CompositingQuality.HighQuality;
24                     g.FillEllipse(br, new Rectangle(Point.Empty, size));
25                     //Pen pen = new Pen(Color.Red);
26                     //g.DrawEllipse(pen, new Rectangle(Point.Empty, size));
27                 }
28             }
29             return bitmap;
30         }
31         /// <summary>
32         /// 重绘圆形图
33         /// </summary>
34         private void DrawPic_Paint(object sender, PaintEventArgs e)
35         {
36             int ntemp = 2;
37             //根据样本类型，对应颜色
38             Brush brush = new SolidBrush(Color.Red);
39             Pen pen = new Pen(brush);
40             e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
41             e.Graphics.DrawEllipse(pen, new RectangleF(e.ClipRectangle.Left + ntemp,
42             e.ClipRectangle.Top +
43             ntemp, e.ClipRectangle.Width - (2 * ntemp),
44             e.ClipRectangle.Height - (2 * ntemp)));
45             //实心填充
46             Rectangle r = new Rectangle(e.ClipRectangle.Left + ntemp, e.ClipRectangle.Top +
47             ntemp, e.ClipRectangle.Width - (2 * ntemp), e.ClipRectangle.Height - (2 * ntemp));
48             e.Graphics.DrawEllipse(pen, r);
49             e.Graphics.FillEllipse(brush, r);
50         }