asp.net GDI+ 使用PathGradienBrush類實現彩色漸層

標籤：img   oar   phi   images   poi   prot   format   rom   bitmap   

 1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using System.Web; 5 using System.Web.UI; 6 using System.Web.UI.WebControls; 7 using System.Drawing; 8 using System.Drawing.Drawing2D; 9 10 public partial class _Default : System.Web.UI.Page11 {12     protected void Page_Load(object sender, EventArgs e)13     {14         Bitmap bitmap = new Bitmap(400, 200);15         Graphics graphics = Graphics.FromImage(bitmap);16         graphics.Clear(Color.White);17         Point centerPoint = new Point(100, 100);18         int r = 100;19         GraphicsPath path = new GraphicsPath();20         path.AddEllipse(centerPoint.X - r, centerPoint.Y - r, 2 * r, 2 * r);21         PathGradientBrush mypathgradientBrush = new PathGradientBrush(path);22         mypathgradientBrush.CenterPoint = centerPoint;23         mypathgradientBrush.CenterColor = Color.DarkGreen;24         mypathgradientBrush.SurroundColors = new Color[] { Color.Gold };25         graphics.FillEllipse(mypathgradientBrush, centerPoint.X - r, centerPoint.Y - r, 2 * r, 2 * r);26         centerPoint = new Point(300, 100);27         r = 33;28         path = new GraphicsPath();29         path.AddEllipse(centerPoint.X - r, centerPoint.Y - r, 2 * r, 2 * r);30         path.AddEllipse(centerPoint.X - 2*r, centerPoint.Y - 2*r, 4 * r, 4 * r);31         path.AddEllipse(centerPoint.X - 3 * r, centerPoint.Y - 3 * r, 6 * r, 6 * r);32         mypathgradientBrush = new PathGradientBrush(path);33         mypathgradientBrush.CenterPoint = centerPoint;34         mypathgradientBrush.CenterColor = Color.Gold;35         mypathgradientBrush.SurroundColors = new Color[] { Color.Black, Color.Blue, Color.DarkGreen };36         graphics.FillPath(mypathgradientBrush, path);37         System.IO.MemoryStream ms = new System.IO.MemoryStream();38         bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);39         Response.ClearContent();40         Response.ContentType = "image/Jpeg";41         Response.BinaryWrite(ms.ToArray());42     }43 }

 

asp.net GDI+ 使用PathGradienBrush類實現彩色漸層