protected void Button1_Click(object sender, EventArgs e){/*微软为Response对象提供了一个新的方法TransmitFile来解决使用Response.BinaryWrite下载超过400mb的文件时导致Aspnet_wp.exe进程回收而无法成功下载的问题。代码如下：*/Response.ContentType = "application/x-zip-compressed";Response.AddHeader("Content-Disposition", "attachment;filename=z.zip");string filename = Server.MapPath("DownLoad/aaa.zip");Response.TransmitFile(filename);}//WriteFile实现下载protected void Button2_Click(object sender, EventArgs e){/*using System.IO;*/string fileName = "aaa.zip";//客户端保存的文件名string filePath = Server.MapPath("DownLoad/aaa.zip");//路径
FileInfo fileInfo = new FileInfo(filePath);Response.Clear();Response.ClearContent();Response.ClearHeaders();Response.AddHeader("Content-Disposition", "attachment;filename=" + fileName);Response.AddHeader("Content-Length", fileInfo.Length.ToString());Response.AddHeader("Content-Transfer-Encoding", "binary");Response.ContentType = "application/octet-stream";Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312");Response.WriteFile(fileInfo.FullName);Response.Flush();Response.End();}//WriteFile分块下载protected void Button3_Click(object sender, EventArgs e){string fileName = "aaa.zip";//客户端保存的文件名string filePath = Server.MapPath("DownLoad/aaa.zip");//路径
System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);if (fileInfo.Exists == true){const long ChunkSize = 102400;//100K 每次读取文件，只读取100Ｋ，这样可以缓解服务器的压力byte[] buffer = new byte[ChunkSize];Response.Clear();System.IO.FileStream iStream = System.IO.File.OpenRead(filePath);long dataLengthToRead = iStream.Length;//获取下载的文件总大小Response.ContentType = "application/octet-stream";Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName));while (dataLengthToRead > 0 && Response.IsClientConnected){int lengthRead = iStream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//读取的大小Response.OutputStream.Write(buffer, 0, lengthRead);Response.Flush();dataLengthToRead = dataLengthToRead - lengthRead;}Response.Close();}}//流方式下载protected void Button4_Click(object sender, EventArgs e){string fileName = "aaa.zip";//客户端保存的文件名string filePath = Server.MapPath("DownLoad/aaa.zip");//路径//以字符流的形式下载文件 需要使用FileAccess.Read，不然第二次会锁定文件无法打开FileStream fs = new FileStream(filePath, FileMode.Open,FileAccess.Read);byte[] bytes = new byte[(int)fs.Length];fs.Read(bytes, 0, bytes.Length);fs.Close();Response.ContentType = "application/octet-stream";//通知浏览器下载文件而不是打开Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8));Response.BinaryWrite(bytes);Response.Flush();Response.End();}