各位做网站的大侠们，来看一下吧！！急

//提供下载的文件，不编码的话文件名会乱码
        private string fileName = HttpContext.Current.Server.UrlEncode("规范.rar");
        private string filePath = HttpContext.Current.Server.MapPath("规范.rar");
        //使用TransmifFile下载文件
        protected void btnDL1_Click(object sender, EventArgs e)
        {
            FileInfo info = new FileInfo(filePath);
            long fileSize = info.Length;
            Response.Clear();
            Response.ContentType = "application/x-zip-compressed";
            Response.AddHeader("Content-Disposition", "attachment;filename="+ fileName);
            //不指明Content-Length用Flush的话不会显示下载进度
            Response.AddHeader("Content-Length", fileSize.ToString());
            Response.TransmitFile(filePath, 0, fileSize);
            Response.Flush();
            Response.Close();
        }

        //使用WriteFile下载文件
        protected void btnDL2_Click(object sender, EventArgs e)
        {
            FileInfo info = new FileInfo(filePath);
            long fileSize = info.Length;
            Response.Clear();
            Response.ContentType = "application/octet-stream";
            Response.AddHeader("Content-Disposition", "attachement;filename=" + fileName);
            //指定文件大小
            Response.AddHeader("Content-Length", fileSize.ToString());
            Response.WriteFile(filePath, 0, fileSize);
            Response.Flush();
            Response.Close();
        }

        //使用OutputStream.Write分块下载文件
        protected void btnDL3_Click(object sender, EventArgs e)
        {
            //指定块大小
            long chunkSize = 102400;
            //建立一个100K的缓冲区
            byte[] buffer = new byte[chunkSize];
            //已读的字节数
            long dataToRead = 0;
            FileStream stream = null;
            try
            {
                //打开文件
                stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read);
                dataToRead = stream.Length;

                //添加Http头
                Response.ContentType = "application/octet-stream";
                Response.AddHeader("Content-Disposition", "attachement;filename=" + fileName);
                Response.AddHeader("Content-Length", dataToRead.ToString());

                while (dataToRead > 0)
                {
                    if (Response.IsClientConnected)
                    {
                        int length = stream.Read(buffer, 0, Convert.ToInt32(chunkSize));
                        Response.OutputStream.Write(buffer, 0, length);
                        Response.Flush();
                        Response.Clear();
                        dataToRead -= length;
                    }
                    else
                    {
                        //防止client失去连接
                        dataToRead = -1;
                    }
                }
            }
            catch (Exception ex)
            {
                Response.Write("Error:" + ex.Message);
            }
            finally
            {
                if (stream != null)
                {
                    stream.Close();
                }
                Response.Close();
            }
        }

        //使用BinaryWrite下载文件，大文件效率不行
        protected void btnDL4_Click(object sender, EventArgs e)
        {
            FileStream stream = null;
            try
            {
                //读文件,大文件一次读入会占用大量内存
                stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read);
                byte[] bytes = new byte[stream.Length];
                stream.Read(bytes, 0, bytes.Length);
                stream.Close();

                //添加Http头
                Response.ContentType = "application/octet-stream";
                Response.AddHeader("Content-Disposition", "attachement;filename=" + fileName);
                Response.AddHeader("Content-Length", bytes.Length.ToString());
                Response.BinaryWrite(bytes);
                Response.Flush();
            }
            catch (Exception ex)
            {
                Response.Write("Error:" + ex.Message);
            }
            finally
            {
                if (stream != null)
                {
                    stream.Close();
                }
                Response.Close();
            }
        }
        //使用BinaryWrite分块下载文件
    protected void btnDL5_Click(object sender, EventArgs e)
    {
        //指定区块和缓冲区
        long chunkSize = 102400;
        byte[] buffer = new byte[chunkSize];
        FileStream stream = null;
        long dataToRead = 0;
        try
        {
            stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read);
            dataToRead = stream.Length;
            //添加Http头
            Response.ContentType = "application/octet-stream";
            Response.AddHeader("Content-Disposition", "attachement;filename=" + fileName);
            Response.AddHeader("Content-Length", dataToRead.ToString());            while (dataToRead > 0)
            {
                if (Response.IsClientConnected)
                {
                    int length = stream.Read(buffer, 0, Convert.ToInt32(chunkSize));
                    Response.BinaryWrite(buffer);
                    Response.Flush();
                    Response.Clear();                    dataToRead -= length;
                }
                else
                {
                    dataToRead = -1;
                }
            }        }
        catch (Exception ex)
        {
            Response.Write("Error:" + ex.Message);
        }
        finally
        {
            if (stream != null)
            {
                stream.Close();
            }
            Response.Close();
        }
    }

修改下~~   private   void   DownLoadFile()
                  {
                          try
                          {
                                  WebClient   client   =   new   WebClient();

                                  if   (!Directory.Exists(Application.StartupPath   +   @"\update"))
                                  {
                                          Directory.CreateDirectory(Application.StartupPath   +   @"\update");
                                  }
                                  for   (int   i   =   0;   i   <=   this.listView1.Items.Count   -   1;   i++)
                                  {
                                          string   fileName   =   this.listView1.Items[i].SubItems[0].Text;
                                          string   url   =   @"http://172.16.120.155/update/UpdateFile/"   +   fileName;
                                          string   file   =   Application.StartupPath   +   "\\update\\"   +   fileName;
                                          this.label2.Text   =   "正在下载："   +   fileName;

                                          Stream   myStream   =   client.OpenRead(url);
                                          byte[]   bBuffer   =   new   byte[10240];
                                          int   nRealCount   =   0;
                                          DateTime   dtStart=DateTime.Now   ;
                                          TimeSpan   ts;
                                          int   lenth   =   Convert.ToInt32(this.listView1.Items[i].SubItems[1].Text.ToString());
                                          int   cur   =   0;
                                          progressBar1.Value   =   0;
                                          FileStream   fs   =   new   FileStream(file,   FileMode.OpenOrCreate,   FileAccess.Write);
                                          //do
                                          //{
                                          //         dtStart   =   DateTime.Now;
                                          //         nRealCount   =   myStream.Read(bBuffer,   0,   bBuffer.Length);
                                          //         if   (nRealCount   >   0)
                                          //         {
                                          //                 fs.Write(bBuffer,   0,   nRealCount);
                                          //         }
                                          //         ts   =   DateTime.Now   -   dtStart;
                                          //         cur   =   cur   +   nRealCount;
                                          //         double   pe   =   cur;
                                          //         pe   =   pe   *   100   /   lenth;
                                          //         int   va   =   Convert.ToInt32(pe);
                                          //         progressBar1.Value   =   va;
                                          //         this.label2.Text   =   "正在下载："   +   fileName   +   "       "   +   cur   /   1024   +   "   KB/"   +   lenth   /   1024   +   "   KB";
                                          //         MessageBox.Show(""   +   ts.Milliseconds   +   "     "   +   ts.TotalMilliseconds);
                                          //         //   this.label2.Text   =   "正在下载："   +   fileName   +   "       "   +   cur   /   1024   +   "   KB/"   +   lenth   /   1024   +   "   KB"+"     下载速度:"+((double   )nRealCount   /(int)(ts.TotalMilliseconds/1000))   +"   kb/s";
                                          //         //   计算流量可以用   nRealCount   /   ts.Seconds来进行估算
                                          //}
                                          int   value=0;
                                          int   counter   =   1;
                                          do
                                          {
                                                  if   (counter   %   10   ==   0)
                                                  {
                                                          ts   =   DateTime.Now   -   dtStart;

                                                          int   perSecondsValue   =   (int)((double)value   /   (ts.TotalMilliseconds   /   1000))   /   1024;

                                                          this.label3.Text   =   "速度："   +perSecondsValue   +"   k/s";
                                                          dtStart   =   DateTime.Now;
                                                          value   =   0;
                                                  }

                                                  nRealCount   =   myStream.Read(bBuffer,   0,   bBuffer.Length);
                                                  if   (nRealCount   >   0)
                                                  {
                                                          fs.Write(bBuffer,   0,   nRealCount);
                                                  }
                                                  cur   =   cur   +   nRealCount;
                                                  double   pe   =   cur;
                                                  pe   =   pe   *   100   /   lenth;
                                                  int   va   =   Convert.ToInt32(pe);
                                                  progressBar1.Value   =   va;

                                                  this.label2.Text   =   "正在下载："   +   fileName   +   "       "   +   cur   /   1024   +   "   KB/"   +   lenth   /   1024   +   "   KB";

                                                  value   +=   nRealCount;
                                                  counter++;
                                          }
                                          while   (nRealCount   >   0);
                                          fs.Close();
                                          //   client.DownloadFile(url,   file);
                                          this.listView1.Items[i].SubItems.Add("已下载");
                                  }

                                  this.progressBar1.Visible   =   false;
                                  this.label3.Visible   =   false;
                                  this.label2.Text   =   "正在更新文件,请稍后...";
                                  string[]   fileDir   =   Directory.GetFileSystemEntries(Application.StartupPath   +   @"\update");

                                  foreach   (string   str   in   fileDir)
                                  {
                                          int   pos   =   str.LastIndexOf(@"\");
                                          string   FileName   =   str.Substring(pos);
                                          string   FilePath   =   Application.StartupPath   +   FileName;
                                          File.Copy(str,   FilePath,   true);
                                  }

                                  this.label2.Text   =   "程序更新已完成!";

                                  this.label1.Text   =   this.finish;
                                  this.btnNext.Enabled   =   false;
                                  this.listView1.Visible   =   false;
                                  this.btnExit.Text   =   "完成(&F)";
                                  step++;
                          }
                          catch   (Exception   errMsg)
                          {
                                  MessageBox.Show(errMsg.Message);
                          }
                  }

不用放入数据库里面
放在数据库里面只是相对的路径而已
建立一个文件夹
讲上传的东西等于move 进文件夹
然后再上传下载的时候将路径放在数据库就Ok了
还有为了避免网站上传下载的流量大和文件名称相同的问题
可以在上传的路径的代码后面加上当前的时间，截取到毫秒。
不可能会有人在一毫秒上传同样名称的文件吧
这样问题就Ok了

很多方法，但是把文件存到数据库里貌似非常的慢，如果是从文件夹里下载方法如下：
public static void FileDownload(string FileName) //fileName为虚拟路径
{
String FullFileName = System.Web.HttpContext.Current.Server.MapPath(FileName);
FileInfo DownloadFile = new FileInfo(FullFileName);
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();
}
下载,直接调用方法
/////////////////////////////////////////////////
大文件下载
public bool Down(string filepath, string code)
        {
            bool succ = false;            System.IO.Stream iStream = null;            // Buffer to read 10K bytes in chunk:
            byte[] buffer = new Byte[10000];            // Length of the file:
            int length;            // Total bytes to read:
            long dataToRead;            // Identify the file to download including its path.
          //  string filepath = "DownloadFileName";            // Identify the file name.
            string filename = System.IO.Path.GetFileName(filepath);            try
            {
                // Open the file.
                iStream = new System.IO.FileStream(filepath, System.IO.FileMode.Open,
                            System.IO.FileAccess.Read, System.IO.FileShare.Read);
                // Total bytes to read:
                dataToRead = iStream.Length;                Response.ContentType = "application/octet-stream";
                Response.AddHeader("Content-Disposition", "attachment; filename=" + filename);                // Read the bytes.
                while (dataToRead > 0)
                {
                    // Verify that the client is connected.
                    if (Response.IsClientConnected)
                    {
                        // Read the data in buffer.
                        length = iStream.Read(buffer, 0, 10000);                        // Write the data to the current output stream.
                        Response.OutputStream.Write(buffer, 0, length);                        // Flush the data to the HTML output.
                        Response.Flush();                        buffer = new Byte[10000];
                        dataToRead = dataToRead - length;
                    }
                    else
                    {
                        //prevent infinite loop if user disconnects
                        dataToRead = -1;
                    }
                }
            }
            catch (Exception ex)
            {
                // Trap the error, if any.
                Response.Write("Error : " + ex.Message);
            }
            finally
            {
                if (iStream != null)
                {
                    //Close the file.
                    iStream.Close();
                }
            }
            return succ;
        }从数据库下载数据：
string ConnStr = "server=(local);user id=sa;pwd=sa;database=test";
            string strSql = "select * from piclist";
            SqlConnection conn = new SqlConnection(ConnStr);
            conn.Open();            SqlCommand cmd=new SqlCommand(strSql,conn);
            SqlDataReader reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                Response.ContentType = "application/octet-stream";
                Response.BinaryWrite((Byte[])reader["pic"]);
                Response.Write("successful");
            }
             reader.Close();
             conn.Close();
             Response.End();
注意把，下边的改一改，然后建一个下载用的数据流，把字节数组放到流中，就可以了

调试易

各位做网站的大侠们，来看一下吧！！急

解决方案 »