大文件上传之FTP文件上传
我想很多人都知道.net自带的上传控件是不支持大文件上传的,默认情况下是4M,当然你可以通过配置WEB.CONFIG来增大上传大小,但是会影响服务器的性能.这里就大文件上传提供一个解决方案,就是采用FTP上传,FTP协议是支持大文件上传的.再大的都吃得消.因此,我们的目的就是再服务器上配置好FTP服务器.然后上传文件就交给FTP服务器来完成.可以手动在DOS中操作FTP服务器.也可以用代码来操作,下面是一个代码的例子,摘录自MSDN:
FTPState.cs:
using System;
using System.Data;
using System.Configuration;
using System.Threading;
using System.Net;
/**//// <summary>
/// FTPState 的摘要说明
/// </summary>
public class FTPState
...{
private ManualResetEvent wait;
private FtpWebRequest request;
private string fileName;
private Exception operationException = null;
string status;
public FTPState()
...{
wait = new ManualResetEvent(false);
}
public ManualResetEvent OperationComplete
...{
get ...{ return wait; }
}
public FtpWebRequest Request
...{
get
...{
return request;
}
set
...{
request = value;
}
}
public string FileName
...{
get ...{ return fileName; }
set ...{ fileName = value; }
}
public Exception OperationException
...{
get ...{ return operationException; }
set ...{ operationException = value; }
}
public string StateDescription
...{
get ...{ return status; }
set ...{ status = value; }
}
}
FTPsupport.cs:using System;
using System.Data;
using System.Configuration;
using System.Net;
using System.IO;
using System.Threading;
/**//// <summary>
/// FTPsupport 的摘要说明
/// </summary>
public class FTPsupport
...{
public FTPsupport()
...{
//
// TODO: 在此处添加构造函数逻辑
//
}
public static bool ListFilesOnServer(Uri serverUri,ref string message,ref Stream responseStream)
...{
// The serverUri should start with the ftp:// scheme.
if (serverUri.Scheme != Uri.UriSchemeFtp)
...{
return false;
}
// Get the object used to communicate with the server.
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(serverUri);
request.Method = WebRequestMethods.Ftp.ListDirectory;
// Get the ServicePoint object used for this request, and limit it to one connection.
// In a real-world application you might use the default number of connections (2),
// or select a value that works best for your application.
ServicePoint sp = request.ServicePoint;
//Console.WriteLine("ServicePoint connections = {0}.", sp.ConnectionLimit);
sp.ConnectionLimit = 1;
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
//Stream responseStream = null;
// The following streams are used to read the data returned from the server.
StreamReader readStream = null;
try
...{
responseStream = response.GetResponseStream();
readStream = new StreamReader(responseStream, System.Text.Encoding.UTF8);
if (readStream != null)
...{
// Display the data received from the server.
//Console.WriteLine(readStream.ReadToEnd());
message = readStream.ReadToEnd();
}
//Console.WriteLine("List status: {0}", response.StatusDescription);
}
finally
...{
//if (readStream != null)
//{
// readStream.Close();
//}
if (response != null)
...{
response.Close();
}
}
return true;
}
public static bool DelFile(Uri serverUri,ref string result)
...{
if(serverUri.Scheme!=Uri.UriSchemeFtp)
...{
return false;
}
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(serverUri);
request.Method = WebRequestMethods.Ftp.DeleteFile;
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
result = response.StatusDescription;
response.Close();
return true;
}
public static bool FileDownload1(Uri serverUri,ref string content,ref Stream filestream)
...{
if(serverUri.Scheme!=Uri.UriSchemeFtp)
...{
return false;
}
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(serverUri);
request.Method = WebRequestMethods.Ftp.DownloadFile;
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
filestream = response.GetResponseStream();
StreamReader reader = new StreamReader(filestream, System.Text.Encoding.UTF8);
content = reader.ReadToEnd();
response.Close();
return true;
}
public static bool FileDownload(Uri serverUri,ref string filestring)
...{
if (serverUri.Scheme != Uri.UriSchemeFtp)
...{
return false;
}
WebClient request = new WebClient();
request.Credentials = new NetworkCredential("anonymous", "xiao_jun_0820@163.com");
try
...{
byte[] newFileData = request.DownloadData(serverUri);
//这里ref回去的是下载的文件的内容,然后在前台新建一个同类型的文件,把内容写进去就OK了.
filestring = System.Text.Encoding.UTF8.GetString(newFileData);//这个地方可能会有点问题,如果你要下载的文件不是UTF-8形式保存的,则文件内容中的中文将变乱码,那就只能预先将FTP服务器上的文件保存为UTF-8形式.
}
catch(WebException e)
...{
filestring = e.ToString();
}
return true;
}
public static bool FileUpLoad(string fileName,Uri serverUri)
...{
ManualResetEvent waitObject;
FTPState state = new FTPState();
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(serverUri);
request.Method = WebRequestMethods.Ftp.UploadFile;
request.Credentials = new NetworkCredential("anonymous", "xiao_jun_0820@163.com");
state.FileName = fileName;
state.Request = request;
waitObject=state.OperationComplete;
state.Request.BeginGetRequestStream(new AsyncCallback(EndGetStreamCallback),state);
waitObject.WaitOne();
if (state.OperationException != null)
...{
throw state.OperationException;
return false;
}
else
...{
return true;
}
}
private static void EndGetStreamCallback(IAsyncResult ar)
...{
FTPState state = (FTPState)ar.AsyncState;
Stream requestStream;
try
...{
requestStream = state.Request.EndGetRequestStream(ar);
const int buffLength = 2048;
byte[] buffer = new byte;
int count = 0;
int readBytes = 0;
FileStream stream = File.OpenRead(state.FileName);
do
...{
readBytes = stream.Read(buffer, 0, buffLength);
requestStream.Write(buffer, 0, readBytes);
count += readBytes;
}
while (readBytes != 0);
//发送请求之前关闭该请求流
requestStream.Close();
state.Request.BeginGetResponse(new AsyncCallback(EndGetResponseCallback), state);
}
catch (Exception e)
...{
state.OperationException = e;
state.OperationComplete.Set();
return;
}
}
private static void EndGetResponseCallback(IAsyncResult ar)
...{
FTPState state = (FTPState)ar.AsyncState;
FtpWebResponse response = null;
try
...{
response = (FtpWebResponse)state.Request.EndGetResponse(ar);
response.Close();
state.StateDescription = response.StatusDescription;
state.OperationComplete.Set();
}
catch (Exception e)
...{
state.OperationException = e;
state.OperationComplete.Set();
}
}
}
这两个类我稍微做了点点修改,原文请查看MSDN. 版权声明：本文为博主原创文章，未经博主允许不得转载。
页:
[1]