把图片转换成二进制--把二进制转换成图片

把图片转换成二进制--把二进制转换成图片
private void button1_Click( object sender, EventArgs e)
        {
            string path = this .textBox1.Text;
            byte [] imgBytesIn = SaveImage(path);
            ShowImgByByte(imgBytesIn);
            //Parameters.Add("@Photo", SqlDbType.Binary).Value = imgBytesIn;

        }
        //将图片以二进制流
        public byte [] SaveImage(String path)
        {
            FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read); //将图片以文件流的形式进行保存
            BinaryReader br = new BinaryReader(fs);
            byte [] imgBytesIn = br.ReadBytes(( int )fs.Length);  //将流读入到字节数组中
            return imgBytesIn;
        }
        //现实二进制流代表的图片
        public void ShowImgByByte( byte [] imgBytesIn)
        {
            MemoryStream ms = new MemoryStream(imgBytesIn);
            pictureBox1.Image = Image.FromStream(ms);
        }

二、将图片保存到数据库中，并从数据库中读取：
#region 将图片从数据库中读取

         ///

        /// 将图片从数据库中读取
        ///
        /// 要读取图片的学号
        /// pictureBox1控件名
        public void get_photo( string xs_ID, PictureBox ph) //将图片从数据库中读取
        {
            byte [] imagebytes = null ;
            getcon();
            SqlCommand con = new SqlCommand( "select * from S_jiben where S_num='" + xs_ID + "'" , link);
            SqlDataReader dr = con.ExecuteReader();
            while (dr.Read())
            {
                imagebytes =( byte [])dr.GetValue(18);
            }
            dr.Close();
            con_close();
            MemoryStream ms = new MemoryStream(imagebytes);
            Bitmap bmpt = new Bitmap(ms);
            ph.Image = bmpt;
        }
        #endregion
        #region
        public void SaveImage( string MID, OpenFileDialog openF) //将图片以二进制存入数据库中
        {
            string strimg = openF.FileName.ToString();  //记录图片的所在路径
            FileStream fs = new FileStream(strimg, FileMode.Open, FileAccess.Read); //将图片以文件流的形式进行保存
            BinaryReader br = new BinaryReader(fs);
            byte [] imgBytesIn = br.ReadBytes(( int )fs.Length);  //将流读入到字节数组中
            getcon();
            StringBuilder strSql = new StringBuilder();
            strSql.Append( "update S_jiben Set xs_photo=@Photo where S_num=" + MID);
            SqlCommand cmd = new SqlCommand(strSql.ToString(), link);
            cmd.Parameters.Add( "@Photo" , SqlDbType.Binary).Value = imgBytesIn;
            cmd.ExecuteNonQuery();
            con_close();
        }
        #endregion