[c#] [基础] 文件的上传下载删除 若多文件的话 找一个jquery的插件吧~

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using InfoEyeChinatest.Upload;
using System.Web.UI.WebControls;
using System.IO;
using System.Web.UI;
namespace InfoEyeChinatest.dbhelper
{
    public class infoupload : Page
    {
        #region   上传文件
        /// 文件上传存储方式,StoreType.DataBase为存储在数据库表中，StoreType.FileSystem为存储在磁盘中,默认为StoreType.FileSystem
        StoreType Store = StoreType.FileSystem;
        /// <summary>
        /// 上传附件
        /// </summary>
        /// <param name="m_files">上传控件</param>
        protected void DoUpload(FileUpload m_files)
        {
            HttpPostedFile pFile = m_files.PostedFile;
            if (pFile != null)
            {
                IList<FileObj> list = new List<FileObj>();
                string filePath = pFile.FileName;
                string fileExtend = "";
                if (filePath.LastIndexOf(".") >= 0)
                {
                    fileExtend = filePath.Substring(filePath.LastIndexOf(".")).ToLower().Trim();
                }
                string fileName = Path.GetFileName(filePath);
                string strPath = "";
                string Savepath = Server.MapPath("~/UploadFiles/root/");//上传文件存到的系统物理地址
                strPath = Savepath + fileName;
                pFile.SaveAs(strPath);
                string AID = Guid.NewGuid().ToString();

                //获取附件信息
                FileObj f = new FileObj();
                f.AID = AID;
                f.Category = "";
                //f.Description = txtDescription.Text;
                //上传后附件的存储处理
                if (Store == StoreType.DataBase)
                {
                    //附件上传过程中，附件直接写入磁盘中，从磁盘中读取附件内容
                    byte[] buf;
                    FileStream fs = new FileStream(strPath, FileMode.Open, FileAccess.Read);
                    buf = new byte[Convert.ToInt32(pFile.ContentLength)];
                    fs.Read(buf, 0, Convert.ToInt32(pFile.ContentLength));
                    fs.Close();
                    fs.Dispose();
                    if (File.Exists(strPath))
                    {
                        File.Delete(strPath);
                    }
                    f.FileContent = buf;
                }
                else
                {
                    f.FilePath = strPath;
                }
                f.FileExtend = fileExtend;
                f.FileName = fileName;
                f.FileSize = (int)(pFile.ContentLength / 1024);
                f.MimeType = pFile.ContentType;
                f.OwnerId = "2";
                f.Status = "status";
                f.Title = "title";
                f.UserId = "userid";
                f.UserName = "username";

                try
                {
                    f.SortIndex = 0;
                }
                catch
                {
                    f.SortIndex = 0;
                }
                //AIDS.Add(f.AID);
                list.Add(f);

                //flagCancel = false;
                FileObjDA fileObjDA = new FileObjDA("ConnectionString");
                fileObjDA.Insert(list);

            }
        }
        #endregion
        #region  下载文件
        /// <summary>
        /// 下载附件
        /// </summary>
        /// <param name="filename">文件名</param>
        protected void DoDownload(String filename)
        {
            String FullFileName = "";
            FullFileName = System.Web.HttpContext.Current.Server.MapPath("~/UploadFiles/root/" + filename);//这里是你文件在项目中的位置,根目录下就这么写 
            FileInfo DownloadFile = new FileInfo(FullFileName);
            //DownloadFile.Name = "asdasd";
            System.Web.HttpContext.Current.Response.Clear();
            System.Web.HttpContext.Current.Response.ClearHeaders();
            System.Web.HttpContext.Current.Response.Buffer = false;
            System.Web.HttpContext.Current.Response.ContentType = "application/octet-stream";
            System.Web.HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(DownloadFile.FullName, System.Text.Encoding.UTF8));
            System.Web.HttpContext.Current.Response.AppendHeader("Content-Length", DownloadFile.Length.ToString());
            System.Web.HttpContext.Current.Response.WriteFile(DownloadFile.FullName);
            System.Web.HttpContext.Current.Response.Flush();
            System.Web.HttpContext.Current.Response.End();
        }
        #endregion
        #region  删除附件
        /// <summary>
        /// 删除附件
        /// </summary>
        /// <param name="filename">文件名</param>
        protected void DoDelete(string filename)
        {
            String path = "";
            path = System.Web.HttpContext.Current.Server.MapPath("~/UploadFiles/root/" + filename);//这里是你文件在项目中的位置,根目录下就这么写 
            if (File.Exists(path))
            {
                File.Delete(path);
            }
        }
        #endregion
    }
}