private void Form1_Load(object sender, EventArgs e)        {            string file =System.IO.Path.Combine(Environment.CurrentDirectory, @"11.jpg");            try            {                Image i = new Bitmap(file);                pbO.Image = i;                pbD1.Image = WayOne(file);                pbD2.Image = WayTwo(file);                pbS1.Image = WaySOne(file);                pbS2.Image = WaySTwo(file);            }            catch (Exception ex)            {                MessageBox.Show(ex.Message);            }        }        private Bitmap WayOne(string file)        {            using (Image i = new Bitmap(file))            {                Bitmap b = new Bitmap(i.Width, i.Height);                using (Graphics g = Graphics.FromImage(b))                {                    g.FillEllipse(new TextureBrush(i), 0, 0, i.Width, i.Height);                }                return b;            }        }        private Bitmap WayTwo(string file)        {            using (Image i = new Bitmap(file))            {                Bitmap b = new Bitmap(i.Width, i.Height);                using (Graphics g = Graphics.FromImage(b))                {                    g.DrawImage(i, 0, 0, b.Width, b.Height);                    int r = Math.Min(b.Width, b.Height) / 2;                    PointF c = new PointF(b.Width / 2.0F, b.Height / 2.0F);                    for (int h = 0; h < b.Height; h++)                        for (int w = 0; w < b.Width; w++)                            if ((int)Math.Pow(r, 2) < ((int)Math.Pow(w * 1.0 - c.X, 2) + (int)Math.Pow(h * 1.0 - c.Y, 2)))                            {                                b.SetPixel(w, h, Color.Transparent);                            }                }                return b;            }        }        private Bitmap WaySOne(string file)        {            using (Image i = new Bitmap(file))            {                Bitmap b = new Bitmap(i.Width, i.Height);                using (Graphics g = Graphics.FromImage(b))                {                    g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;                    using (System.Drawing.Drawing2D.GraphicsPath p = new System.Drawing.Drawing2D.GraphicsPath(System.Drawing.Drawing2D.FillMode.Alternate))                    {                        p.AddEllipse(0, 0, i.Width, i.Height);                        g.FillPath(new TextureBrush(i), p);                    }                    //g.FillEllipse(new TextureBrush(i), 0, 0, i.Width, i.Height);                }                return b;            }        }        private Bitmap WaySTwo(string file)        {            using (Image i = new Bitmap(file))            {                Bitmap b = new Bitmap(i.Width, i.Height);                using (Graphics g = Graphics.FromImage(b))                {                    g.DrawImage(i, 0, 0, b.Width, b.Height);                    int r = Math.Min(b.Width, b.Height) / 2;                    PointF c = new PointF(b.Width / 2.0F, b.Height / 2.0F);                    for (int h = 0; h < b.Height; h++)                        for (int w = 0; w < b.Width; w++)                            if ((int)Math.Pow(r, 2) < ((int)Math.Pow(w * 1.0 - c.X, 2) + (int)Math.Pow(h * 1.0 - c.Y, 2)))                            {                                b.SetPixel(w, h, Color.Transparent);                            }                    //画背景色圆                    using (Pen p = new Pen(System.Drawing.SystemColors.Control))                        g.DrawEllipse(p, 0, 0, b.Width, b.Height);                }                return b;            }        }