愛流浪的小風

 public class ImageResize
    {
        public static Bitmap Resize(Bitmap originImage, Double times)
        {
            int width = Convert.ToInt32(originImage.Width * times);
            int height = Convert.ToInt32(originImage.Height * times);

            return Process(originImage,originImage.Width,originImage.Height,width,height);
        }

        private static Bitmap Process(Bitmap originImage, int oriwidth, int oriheight,int width,int height)
        {
            Bitmap resizedbitmap = new Bitmap(width, height);
            Graphics g = Graphics.FromImage(resizedbitmap);
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
            g.Clear(Color.Transparent);
            g.DrawImage(originImage, new Rectangle(0, 0, width, height), new Rectangle(0, 0, oriwidth, oriheight), GraphicsUnit.Pixel);
            return resizedbitmap;
        }
    }