C#实现下载功能.doc

C#实现下载功能using System;using System.Data;using System.Configuration;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;using System.IO;public partial class _Default : System.Web.UI.Page protected void Page_Load(object sender, EventArgs e) /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); /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(); /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 byteChunkSize; 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.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, att