/// <summary>
        /// 将图片Image转换成Byte[]
        /// </summary>
        /// <param name="Image">image对象</param>
        /// <param name="imageFormat">后缀名</param>
        /// <returns></returns>
        public static byte[] ImageToBytes(Image Image, System.Drawing.Imaging.ImageFormat imageFormat)
        {

            if (Image == null) { return null; }

            byte[] data = http://www.mamicode.com/null;

            using (MemoryStream ms= new MemoryStream())
            {

                 using (Bitmap Bitmap = new Bitmap(Image))
                {

                    Bitmap.Save(ms, imageFormat);

                    ms.Position = 0;

                    data = http://www.mamicode.com/new byte[ms.Length];

                    ms.Read(data, 0, Convert.ToInt32(ms.Length));

                    ms.Flush();

                }

            }

            return data;

        }

            /// <summary>
            /// byte[]转换成Image
            /// </summary>
            /// <param name="byteArrayIn">二进制图片流</param>
            /// <returns>Image</returns>
            public static System.Drawing.Image byteArrayToImage(byte[] byteArrayIn)
            {
                if (byteArrayIn == null)
                    return null;
                using (System.IO.MemoryStream ms = new System.IO.MemoryStream(byteArrayIn))
                {
                    System.Drawing.Image returnImage = System.Drawing.Image.FromStream(ms);
                    ms.Flush();
                    return returnImage;
                }
            }

    //Image转换Bitmap

   1. Bitmap img = new Bitmap(imgSelect.Image);

   2. Bitmap bmp = (Bitmap)pictureBox1.Image;

//Bitmap转换成Image

using System.IO;

private static System.Windows.Controls.Image Bitmap2Image(System.Drawing.Bitmap Bi)
        {           
            MemoryStream ms = new MemoryStream();
            Bi.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
            BitmapImage bImage = new BitmapImage();
            bImage.BeginInit();
            bImage.StreamSource = new MemoryStream(ms.ToArray());
            bImage.EndInit();
            ms.Dispose();
            Bi.Dispose();
            System.Windows.Controls.Image i = new System.Windows.Controls.Image();
            i.Source = bImage;
            return i ;
        }

//byte[] 转换 Bitmap
 public static Bitmap BytesToBitmap(byte[] Bytes) 
        { 
            MemoryStream stream = null; 
            try 
            { 
                stream = new MemoryStream(Bytes); 
                return new Bitmap((Image)new Bitmap(stream)); 
            } 
            catch (ArgumentNullException ex) 
            { 
                throw ex; 
            } 
            catch (ArgumentException ex) 
            { 
                throw ex; 
            } 
            finally 
            { 
                stream.Close(); 
            } 
        }  
 
//Bitmap转byte[]  
        public static byte[] BitmapToBytes(Bitmap Bitmap) 
        { 
            MemoryStream ms = null; 
            try 
            { 
                ms = new MemoryStream(); 
                Bitmap.Save(ms, Bitmap.RawFormat); 
                byte[] byteImage = new Byte[ms.Length]; 
                byteImage = ms.ToArray(); 
                return byteImage; 
            } 
            catch (ArgumentNullException ex) 
            { 
                throw ex; 
            } 
            finally 
            { 
                ms.Close(); 
            } 
        } 
    } 

Byte[]、Image、Bitmap 之间的相互转换