图片上传/下载，ＤＯＣ．xls文档下载的方法

上传：

       #region 上传文件
        protected string UpPicFile(System.Web.UI.WebControls.FileUpload FileUpControl, ref string fileType)
        {
            if (FileUpControl.HasFile)
            {
                string strErr = "";

                #region 验证
                if (FileUpControl.PostedFile == null)
                {
                    strErr += "对不起，上传文件不能为空！\\n";
                }
                int size = FileUpControl.PostedFile.ContentLength;//大小
                if (size < 1)
                {
                    strErr += "对不起，上传文件不能为空！\\n";
                }
                if (size > 10485760)
                {
                    strErr += "对不起，文件大小不能大于10M！\\n";
                }
                if (strErr != "")
                {
                    QDHotel.Common.MessageBox.Show(this, strErr);
                    return null;
                }
                #endregion

                string UploadFileType = FileUpControl.PostedFile.ContentType;
                string UpFileName = FileUpControl.FileName;
                string picname = DateTime.Now.ToString("yyyyMMddHHmmss") + UpFileName;
                fileType = UploadFileType;
                #region 不同类型UploadFileType

                switch (UploadFileType)
                {
                    case "image/gif":
                    case "image/bmp":
                    case "image/pjpeg":
                        {
                            Stream StreamObject = FileUpControl.PostedFile.InputStream;//建立数据流对像
                            System.Drawing.Image myImage = System.Drawing.Image.FromStream(StreamObject);
                            int w = myImage.Width;
                            int h = myImage.Height;
                        }
                        break;

                    case "application/msword":
                    case "application/vnd.ms-excel":
                        break;


                    default:
                        strErr += "对不起，不允许该文件格式上传！\\n";
                        break;
                }
                #endregion

                if (strErr != "")
                {
                    QDHotel.Common.MessageBox.Show(this, strErr);
                    return null;
                }

                try
                {
                    string path = ADUploadFolder + picname;
                    path = Server.MapPath(path);
                    FileUpControl.PostedFile.SaveAs(path);
                    return picname;
                }
                catch //(Exception ex)
                {
                    return null;
                }

            }
            else
            {
                return null;
            }
        }
        #endregion

下载

   private void ViewImage(string fileType, string fileName, bool forceDownload)
        {
            if (fileType == "application/msword" || fileType == "application/vnd.ms-excel")
            {
                //Response.Redirect("UploadPic/" + fileName);
                //return;
                System.IO.FileStream r = new System.IO.FileStream(Server.MapPath("UploadPic/" + fileName), System.IO.FileMode.Open);
                //设置基本信息 
                Response.Buffer = false;
                Response.AddHeader("Connection", "Keep-Alive");
                Response.ContentType = "application/octet-stream";
                Response.AddHeader("Content-Disposition", "attachment;filename=" + System.IO.Path.GetFileName(Server.MapPath("UploadPic/" + fileName)));
                Response.AddHeader("Content-Length", r.Length.ToString());


                while (true)
                {
                    //开辟缓冲区空间 
                    byte[] buffer = new byte[1024];
                    //读取文件的数据 
                    int leng = r.Read(buffer, 0, 1024);
                    if (leng == 0)//到文件尾，结束 
                        break;
                    if (leng == 1024)//读出的文件数据长度等于缓冲区长度，直接将缓冲区数据写入 
                        Response.BinaryWrite(buffer);
                    else
                    {
                        //读出文件数据比缓冲区小，重新定义缓冲区大小，只用于读取文件的最后一个数据块 
                        byte[] b = new byte[leng];
                        for (int i = 0; i < leng; i++)
                            b[i] = buffer[i];
                        Response.BinaryWrite(b);
                    }
                }
                r.Close();//关闭下载文件 
                Response.End();//结束文件下载 
            }
            Response.Clear();
            if (forceDownload)
            {
                Response.AppendHeader("Content-Disposition", "attachment; filename=" + fileName);
            }
            else
            {
                Response.AppendHeader("Content-Disposition", "filename=" + fileName);
            }

            using (System.Drawing.Image image = System.Drawing.Image.FromFile(MapPath(picDic + fileName)))
            {
                if (image.RawFormat.Equals(ImageFormat.Bmp))
                {
                    Response.ContentType = "image/bmp";
                }
                else
                {
                    if (image.RawFormat.Equals(ImageFormat.Gif))
                    {
                        Response.ContentType = "image/gif";
                    }
                    else
                    {
                        if (image.RawFormat.Equals(ImageFormat.Jpeg))
                        {
                            Response.ContentType = "image/jpeg";
                        }
                        else
                        {
                            if (image.RawFormat.Equals(ImageFormat.Png))
                            {
                                Response.ContentType = "image/png";
                            }
                            else
                            {
                                Response.ContentType = "application/octet-stream";
                            }
                        }
                    }

                    image.Save(Response.OutputStream, image.RawFormat);
                }
            }
        }