1、求一個 ASP.NET C# 下載文件的函數，參數是要下載的文件在伺服器中的路徑，一調用此函數，客
不同瀏覽器寫法還不一樣
public static string Get_NewFileName(string filename)
{
string userAgent = HttpContext.Current.Request.UserAgent;
string new_filename = HttpUtility.UrlEncode(filename);
string rtn = "filename="" + new_filename + """;
if (userAgent != null)
{
userAgent = userAgent.ToLower();
if (userAgent.IndexOf("opera") != -1)
{
rtn = "filename*=UTF-8''" + new_filename;
}
else if (userAgent.IndexOf("mozilla") != -1)
{
rtn = "filename*=UTF-8''" + new_filename;
}
}
return rtn;
}
public static void DownFile(string filename)
{
Stream iStream = null;
byte[] buffer = new byte[10000];
int length;
long dataToRead;
iStream = new FileStream(filename, FileMode.Open, FileAccess.Read, FileShare.Read);
dataToRead = iStream.Length;
HttpContext.Current.Response.ContentType = "application/octet-stream";
string filename2;
string[] filename3 = ShareProject.Char.CharHandle.splitfun(filename, ".");
filename2 = "下載文件名" + "." + filename3[filename3.Length - 1];//下載時顯示的名稱
filename2 = Get_NewFileName(filename2);
HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; " + filename2);
while (dataToRead > 0)
{
if (HttpContext.Current.Response.IsClientConnected)
{
length = iStream.Read(buffer, 0, 10000);
HttpContext.Current.Response.OutputStream.Write(buffer, 0, length);
HttpContext.Current.Response.Flush();
buffer = new Byte[10000];
dataToRead = dataToRead - length;
}
else
{
dataToRead = -1;
}
}
iStream.Close();
iStream.Dispose();
HttpContext.Current.Response.End();
}
2、C#下載伺服器指定文件夾下的所有文件
這個文件夾要有目錄瀏覽的許可權（或者必須有一個文件來指明所有的文件名），否則單純的只知道一個地址當然是不可能下載的
3、用c#怎樣從伺服器下載文件，並保存為相應的類型
C#從伺服器下載文件可以使用下面4個方法：TransmitFile、WriteFile、WriteFile和流方式下載文件，並保存為相應類型，方法如下：
1、TransmitFile實現下載
protected void Button1_Click(object sender, EventArgs e)
{
/*
微軟為Response對象提供了一個新的方法TransmitFile來解決使用Response.BinaryWrite
下載超過400mb的文件時導致Aspnet_wp.exe進程回收而無法成功下載的問題。
代碼如下：
*/
Response.ContentType = "application/x-zip-compressed";
Response.AddHeader("Content-Disposition", "attachment;filename=z.zip");
string filename = Server.MapPath("DownLoad/z.zip");
Response.TransmitFile(filename);
}
2、WriteFile實現下載
protected void Button2_Click(object sender, EventArgs e)
{
/*
using System.IO;
*/
string fileName = "asd.txt";//客戶端保存的文件名
string filePath = Server.MapPath("DownLoad/aaa.txt");//路徑
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();
}
3、WriteFile分塊下載
protected void Button3_Click(object sender, EventArgs e)
{
string fileName = "aaa.txt";//客戶端保存的文件名
string filePath = Server.MapPath("DownLoad/aaa.txt");//路徑
System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);
if (fileInfo.Exists == true)
{
const long ChunkSize = 102400;//100K 每次讀取文件，只讀取100K，這樣可以緩解伺服器的壓力
byte[] buffer = new byte[ChunkSize];
Response.Clear();
System.IO.FileStream iStream = System.IO.File.OpenRead(filePath);
long dataLengthToRead = iStream.Length;//獲取下載的文件總大小
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));//讀取的大小
Response.OutputStream.Write(buffer, 0, lengthRead);
Response.Flush();
dataLengthToRead = dataLengthToRead - lengthRead;
}
Response.Close();
}
}
4、流方式下載
protected void Button4_Click(object sender, EventArgs e)
{
string fileName = "aaa.txt";//客戶端保存的文件名
string filePath = Server.MapPath("DownLoad/aaa.txt");//路徑
//以字元流的形式下載文件
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";
//通知瀏覽器下載文件而不是打開
Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8));
Response.BinaryWrite(bytes);
Response.Flush();
Response.End();
}
4、C#從伺服器打包下載文件
學習學習！
5、asp.net 如何實現將伺服器上的文件下載到本地？
給你提供一點代碼：
string fileURL = this.Server.MapPath("你要下載的文件路徑");//文件路徑，可用相對路徑
FileInfo fileInfo = new FileInfo(fileURL);
Response.Clear();
Response.AddHeader("content-disposition", "attachment;filename=" +
Server.UrlEncode(fileInfo.Name.ToString()));//文件名
Response.AddHeader("content-length", fileInfo.Length.ToString());//文件大小
Response.ContentType = "application/octet-stream";
Response.ContentEncoding = System.Text.Encoding.Default;
Response.WriteFile(fileURL);
6、ASP.NET如何下載伺服器端的文件？比如下載網站根目錄下的「1.txt」到桌面上，求詳細代碼
給你提供一點代碼：
string fileURL = this.Server.MapPath("你要下載的文件路徑");//文件路徑，可用相對路徑
FileInfo fileInfo = new FileInfo(fileURL);
Response.Clear();
Response.AddHeader("content-disposition", "attachment;filename=" + Server.UrlEncode(fileInfo.Name.ToString()));//文件名
Response.AddHeader("content-length", fileInfo.Length.ToString());//文件大小
Response.ContentType = "application/octet-stream";
Response.ContentEncoding = System.Text.Encoding.Default;
Response.WriteFile(fileURL);
天下數據--專業運營香港伺服器、韓國伺服器、美國伺服器等等海外優質伺服器！
7、C#從伺服器上下載一個rar文件 怎麼弄
看你的是ftp下載還是http下載？
FTP方式下載參考：
http://www.cnblogs.com/wang726zq/archive/2012/07/30/ftp.html
Http方式下載參考：
http://.baidu.com/link?url=wNBSRQG_vNwTfbxCUr_
8、asp.net如何實現將伺服器上的文件下載到本地？
給你提供一點代碼：
string fileURL = this.Server.MapPath("你要下載的文件路徑");//文件路徑，可用相對路徑
FileInfo fileInfo = new FileInfo(fileURL);
Response.Clear();
Response.AddHeader("content-disposition", "attachment;filename=" + Server.UrlEncode(fileInfo.Name.ToString()));//文件名
Response.AddHeader("content-length", fileInfo.Length.ToString());//文件大小
Response.ContentType = "application/octet-stream";
Response.ContentEncoding = System.Text.Encoding.Default;
Response.WriteFile(fileURL);