超实用Image类

using System;    using System.Drawing;    using System.Drawing.Imaging;    using System.IO;    using System.Runtime.InteropServices;

    public static class ImageHelper    {        private static float[][] ColorMatrix = null;

        static ImageHelper()        {            float[][] numArray = new float[5][];            numArray[0] = new float[] { 0.299f, 0.299f, 0.299f, 0f, 0f };            numArray[1] = new float[] { 0.587f, 0.587f, 0.587f, 0f, 0f };            numArray[2] = new float[] { 0.114f, 0.114f, 0.114f, 0f, 0f };            float[] numArray2 = new float[5];            numArray2[3] = 1f;            numArray[3] = numArray2;            numArray2 = new float[5];            numArray2[4] = 1f;            numArray[4] = numArray2;            ColorMatrix = numArray;        }

        public static Bitmap ConstructRGB24Bitmap(byte[] coreData, int width, int height)        {            Bitmap bitmap = new Bitmap(width, height, PixelFormat.Format24bppRgb);            BitmapData bitmapdata = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.WriteOnly, PixelFormat.Format24bppRgb);            Marshal.Copy(coreData, 0, bitmapdata.Scan0, coreData.Length);            bitmap.UnlockBits(bitmapdata);            return bitmap;        }

        public static Image Convert(byte[] buff)        {            MemoryStream stream = new MemoryStream(buff);            Image image = Image.FromStream(stream);            stream.Close();            return image;        }

        public static byte[] Convert(Image img)        {            Image image = CopyImageDeeply(img);            MemoryStream stream = new MemoryStream();            image.Save(stream, ImageFormat.Jpeg);            byte[] buffer = stream.ToArray();            stream.Close();            image.Dispose();            return buffer;        }

        public static Bitmap ConvertToGrey(Image origin)        {            Bitmap image = new Bitmap(origin);            Graphics graphics = Graphics.FromImage(image);            ImageAttributes imageAttr = new ImageAttributes();            System.Drawing.Imaging.ColorMatrix newColorMatrix = new System.Drawing.Imaging.ColorMatrix(ColorMatrix);            imageAttr.SetColorMatrix(newColorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);            graphics.DrawImage(image, new Rectangle(0, 0, image.Width, image.Height), 0, 0, image.Width, image.Height, GraphicsUnit.Pixel, imageAttr);            graphics.Dispose();            return image;        }

        public static Icon ConvertToIcon(Image img, int iconLength)        {            using (Bitmap bitmap = new Bitmap(img, new Size(iconLength, iconLength)))            {                return Icon.FromHandle(bitmap.GetHicon());            }        }

        public static Image ConvertToJPG(Image img)        {            MemoryStream stream = new MemoryStream();            img.Save(stream, ImageFormat.Jpeg);            Image image = Image.FromStream(stream);            stream.Close();            return image;        }

        public static Image CopyImageDeeply(Image img)        {            Bitmap image = new Bitmap(img.Width, img.Height, img.PixelFormat);            Graphics graphics = Graphics.FromImage(image);            graphics.DrawImage(img, 0, 0, img.Width, img.Height);            graphics.Dispose();            return image;        }

        public static byte[] GetRGB24CoreData(Bitmap bm)        {            byte[] destination = new byte[(bm.Width * bm.Height) * 3];            BitmapData bitmapdata = bm.LockBits(new Rectangle(0, 0, bm.Width, bm.Height), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);            Marshal.Copy(bitmapdata.Scan0, destination, 0, destination.Length);            bm.UnlockBits(bitmapdata);            return destination;        }

        public static bool IsGif(Image img)        {            FrameDimension dimension = new FrameDimension(img.FrameDimensionsList[0]);            return (img.GetFrameCount(dimension) > 1);        }

        public static byte[] ReviseRGB24Data(byte[] origin, Size originSize, Size newSize)        {            Bitmap image = ConstructRGB24Bitmap(origin, originSize.Width, originSize.Height);            Bitmap bitmap2 = new Bitmap(newSize.Width, newSize.Height);            Graphics graphics = Graphics.FromImage(bitmap2);            graphics.DrawImage(image, 0f, 0f, new RectangleF(0f, 0f, (float) newSize.Width, (float) newSize.Height), GraphicsUnit.Pixel);            graphics.Dispose();            return GetRGB24CoreData(bitmap2);        }

        public static void Save(Image img, string path, ImageFormat format)        {            if ((img != null) && (path != null))            {                CopyImageDeeply(img).Save(path, format);            }        }    }

从db里取出image类型字段：

HeadImageData =  dr["HeadImageData"] as byte[] ?? null