using System.IO;

//读filename到byte[]

        private byte[] ReadFile(string fileName)

        {

            FileStream pFileStream = null;

            byte[] pReadByte = new byte[0];

            try

            {

                pFileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read);

                BinaryReader r = new BinaryReader(pFileStream);

                r.BaseStream.Seek(0, SeekOrigin.Begin);    //将文件指针设置到文件开

                pReadByte = r.ReadBytes((int)r.BaseStream.Length);

                return pReadByte;

            }

            catch

            {

                return pReadByte;

            }

            finally

            {

                if (pFileStream != null)

                    pFileStream.Close();

            }

        }

        //写byte[]到fileName

        private bool writeFile(byte[] pReadByte, string fileName)

        {

            FileStream pFileStream = null;

 

            try

            {

                pFileStream = new FileStream(fileName, FileMode.OpenOrCreate);

                pFileStream.Write(pReadByte, 0, pReadByte.Length);

 

            }

            catch

            {

                return false;

            }

            finally

            {

                if (pFileStream != null)

                    pFileStream.Close();

            }

            return true;

        }

         测试

        private void button6_Click(object sender, EventArgs e)

        {

             //by 闫磊 Email:Landgis@126.com,yanleigis@21cn.com 2007.11.23

 

byte[] b = ReadFile(@"c:\u.jpg");

            if (writeFile(b, @"c:\u1.jpg"))

            {

                MessageBox.Show("成功");

            }

            else { MessageBox.Show("失败"); }

        }