读取图片的DLL

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlTypes;
using System.Drawing;
using System.IO;
namespace NJ_MF_ClassLib
{
    public class tif
    {
        //private System.Windows.Forms.PictureBox pictureBox1;
        public static byte[] tiftojpg(byte[] _bin)
        {
            // System.Windows.Forms.PictureBox picbox = new System.Windows.Forms.PictureBox();
            // System.IO.BinaryReader binReader = new System.IO.BinaryReader();
            // binReader.Read();
            // Stream s = new MemoryStream();
            // SqlBytes bytes = new SqlBytes(_bin);
            // System.IO.File.WriteAllBytes(@"C:\a.bin", newBin);
            // StreamWriter sw = new StreamWriter(@"C:\1.txt", true);
            // sw.WriteLine("111111111111");
            // sw.WriteLine(_bin.Length.ToString());
            // memorystream.Read(byteFileflag,0,2);
            // byteFileflag.Equals(0x4949);
            // picbox.Image = System.Drawing.Image.FromStream(s);
            // System.IO.File.WriteAllBytes(@"C:\a.bin", newBin);
            // bmp2.Save(@"C:\test.jpg");
            //----------------------------------------------
            if (_bin == null)
                return _bin;
            byte[] newBin  = new byte[_bin.Length-7];
            Array.Copy(_bin,7, newBin, 0,newBin.Length);                                       
            byte[] byteFileflag = new byte[2];           
            Array.Copy(newBin, 0, byteFileflag, 0, 2);           
            byte byteFlag = byteFileflag[0];
            if (byteFlag == 0x49)
            {
                MemoryStream memorystream = new MemoryStream(newBin);
                memorystream.Position = 0;

                MemoryStream retMemoryStream = new MemoryStream();
                Bitmap bmp = new Bitmap(memorystream);

                bmp.Save(retMemoryStream, System.Drawing.Imaging.ImageFormat.Jpeg);              
                byte[] retBinary = new byte[retMemoryStream.Length];
                retMemoryStream.Position = 0;
                retMemoryStream.Read(retBinary, 0, (int)retMemoryStream.Length);

                retMemoryStream.Close();
                retMemoryStream.Dispose();

                memorystream.Close();
                memorystream.Dispose();
                return retBinary;
            }
            else
            {
                return newBin;
            }

        }

        static int IndexOf(byte[] s, byte[] pattern)
        {
            int slen = s.Length;
            int plen = pattern.Length;
            for (int i = 0; i <= slen - plen; i++)
            {
                for (int j = 0; j < plen; j++)
                {
                    if (s[i + j] != pattern[j]) goto next;
                }
                return i;
            next: ;
            }
            return -1;
        }
    }
}