圖片更改大小保存至數據庫並讀取

//保存圖片至數據庫

           HttpPostedFile upfile = null ;
            byte[] bt = null;
            if (context.Request.Files.Count > 0)
            {
                upfile = context.Request.Files[0];
                System.Drawing.Image imgOutput = System.Drawing.Bitmap.FromStream(upfile.InputStream);
                //修改圖片寬度爲800，高度等比例縮放
                System.Drawing.Image imgOutput2 = imgOutput.GetThumbnailImage(800,imgOutput.Height * 800 / imgOutput.Width, null, IntPtr.Zero);
                MemoryStream ms = new MemoryStream();
                imgOutput2.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
                bt = ms.ToArray();//SQL image類型直接保存
            }

//讀取

Response.Clear();
                Response.ContentType = "image/gif";
                Response.BinaryWrite(sqlimg);