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 }
