一、//TransmitFile实现下载     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/z.zip");        Response.TransmitFile(filename);    }二、//WriteFile实现下载     protected void Button2_Click(object sender, EventArgs e)    {        /*         using System.IO;        */        string fileName = "asd.txt";//客户端保存的文件名         string filePath = Server.MapPath("DownLoad/aaa.txt");//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();    }三、   //WriteFile分块下载     protected void Button3_Click(object sender, EventArgs e)    {        string fileName = "aaa.txt";//客户端保存的文件名         string filePath = Server.MapPath("DownLoad/aaa.txt");//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();        }    }四、//流方式下载     protected void Button4_Click(object sender, EventArgs e)    {        string fileName = "aaa.txt";//客户端保存的文件名         string filePath = Server.MapPath("DownLoad/aaa.txt");//路径        //以字符流的形式下载文件         FileStream fs = new FileStream(filePath, FileMode.Open);        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();    }//----------------------------------------------------------public void DownloadFile( System.Web.UI.Page WebForm,String FileNameWhenUserDownload ,String FileBody ){　　WebForm.Response.ClearHeaders();　　WebForm.Response.Clear();　　WebForm.Response.Expires = 0;　　WebForm.Response.Buffer = true;　　WebForm.Response.AddHeader("Accept-Language", "zh-tw");　　//‘文件名称　　WebForm.Response.AddHeader("content-disposition", "attachment; filename=‘"+System.Web.HttpUtility.UrlEncode(FileNameWhenUserDownload, System.Text.Encoding.UTF8)+"‘");　　WebForm.Response.ContentType = "Application/octet-stream";　　//‘文件内容　　WebForm.Response.Write(FileBody);//-----------    WebForm.Response.End();}//上面这段代码是下载一个动态产生的文本文件，若这个文件已经存在于服务器端的实体路径，则可以通过下面的函数：public void DownloadFileByFilePath( System.Web.UI.Page WebForm,String FileNameWhenUserDownload ,String FilePath ){　　WebForm.Response.ClearHeaders();　　WebForm.Response.Clear();　　WebForm.Response.Expires = 0;    WebForm.Response.Buffer = true;　　WebForm.Response.AddHeader("Accept-Language", "zh-tw");　　//文件名称　　WebForm.Response.AddHeader("content-disposition", "attachment; filename=‘" + System.Web.HttpUtility.UrlEncode(FileNameWhenUserDownload, System.Text.Encoding.UTF8) +"‘" );　　WebForm.Response.ContentType = "Application/octet-stream";　　//文件内容　　WebForm.Response.Write(System.IO.File.Rea}dAllBytes(FilePath));//---------　　WebForm.Response.End();｝