Asp.net2.0中FTP支持断点续传源码

/*****************************************************************

// Copyright (C) 2006-2007 Newegg Corporation

// All rights reserved.

// 

// Author:       Charles Ge (Charles.Y.Ge@Newegg.com)

// Create Date:  04/12/2007 15:33:42

// Usage: DFIS Ftp Client Service,add ftp site,upload files,download files

//

// RevisionHistory

// Date         Author               Description

// 

*****************************************************************/

using System;

using System.IO;

using System.Net;

using System.Net.Security;

using System.Collections;

using System.Collections.Generic;

using System.Security.Cryptography.X509Certificates;

using System.Web;

using System.Web.Configuration;

public sealed class FtpClientService

{

    #region Internal Members





private NetworkCredential certificate;



#endregion





/// <summary>



/// 构造函数，提供初始化数据的功能，打开Ftp站点



/// </summary>



public FtpClientService()

{

certificate = new NetworkCredential(WebConfigurationManager.AppSettings["UserName"], WebConfigurationManager.AppSettings["PassWord"]);

}



/// <summary>



/// 创建FTP请求



/// </summary>



/// <param name="uri">ftp://myserver/upload.txt</param>



/// <param name="method">Upload/Download</param>



/// <returns></returns>



private FtpWebRequest CreateFtpWebRequest(Uri uri, string method)

{

FtpWebRequest ftpClientRequest = (FtpWebRequest) WebRequest.Create(uri);



ftpClientRequest.Proxy = null;

ftpClientRequest.Credentials = certificate;

ftpClientRequest.KeepAlive = true;

ftpClientRequest.UseBinary = true;

ftpClientRequest.UsePassive = true;

ftpClientRequest.Method = method;



//ftpClientRequest.Timeout = -1;





return ftpClientRequest;

}

    #region 支持断点续传





public bool UploadFile(string sourceFile, Uri destinationPath, int offSet, string ftpMethod)

{

try

{

FileInfo file = new FileInfo(sourceFile);

Uri uri = new Uri(destinationPath.AbsoluteUri + "/" + file.Name);

FtpWebRequest request = CreateFtpWebRequest(uri, ftpMethod);

request.ContentOffset = offSet;

Stream requestStream = request.GetRequestStream();//需要获取文件的流



FileStream fileStream = new FileStream(sourceFile, FileMode.Open, FileAccess.Read);//创建存储文件的流



int sourceLength = (int) fileStream.Length;

offSet = CopyDataToDestination(fileStream, requestStream, offSet);

WebResponse response = request.GetResponse();

response.Close();

if (offSet != 0)

{

UploadFile(sourceFile, destinationPath, offSet, WebRequestMethods.Ftp.AppendFile);

}

}

catch (Exception ex)

{

ex.ToString();

return false;

}



return true;

}



private int CopyDataToDestination(Stream sourceStream, Stream destinationStream, int offSet)

{

try

{

int sourceLength = (int) sourceStream.Length;

int length = sourceLength - offSet;

byte[] buffer = new byte[length + offSet];

int bytesRead = sourceStream.Read(buffer, offSet, length);

while (bytesRead != 0)

{

destinationStream.Write(buffer, 0, bytesRead);

bytesRead = sourceStream.Read(buffer, 0, length);

length = length - bytesRead;

offSet = (bytesRead == 0) ? 0 : (sourceLength - length);//(length - bytesRead);                  



}

}

catch (Exception ex)

{

string error = ex.ToString();

return offSet;

}

finally

{

destinationStream.Close();

sourceStream.Close();

}

return offSet;

}

    #endregion



}