C# ftp 服务器上传下载文件

/// <summary>
/// 上传文件
/// </summary>
/// <param name="fileinfo">需要上传的文件</param>
/// <param name="targetDir">目标路径</param>
/// <param name="hostname">ftp地址</param>
/// <param name="username">ftp用户名</param>
/// <param name="password">ftp密码</param>
public static void UploadFile(FileInfo fileinfo, string targetDir, string hostname, string username, string password)
{
//1. check target
string target;
if (targetDir.Trim() == "")
{
return;
}
target = Guid.NewGuid().ToString(); //使用临时文件名

string URI = "FTP://" + hostname + "/" + targetDir + "/" + target;
///WebClient webcl = new WebClient();
System.Net.FtpWebRequest ftp = GetRequest(URI, username, password);

//设置FTP命令 设置所要执行的FTP命令，
//ftp.Method = System.Net.WebRequestMethods.Ftp.ListDirectoryDetails;//假设此处为显示指定路径下的文件列表
ftp.Method = System.Net.WebRequestMethods.Ftp.UploadFile;
//指定文件传输的数据类型
ftp.UseBinary = true;
ftp.UsePassive = true;

//告诉ftp文件大小
ftp.ContentLength = fileinfo.Length;
//缓冲大小设置为2KB
const int BufferSize = 2048;
byte[] content = new byte[BufferSize - 1 + 1];
int dataRead;

//打开一个文件流 (System.IO.FileStream) 去读上传的文件
using (FileStream fs = fileinfo.OpenRead())
{
try
{
//把上传的文件写入流
using (Stream rs = ftp.GetRequestStream())
{
do
{
//每次读文件流的2KB
dataRead = fs.Read(content, 0, BufferSize);
rs.Write(content, 0, dataRead);
} while (!(dataRead < BufferSize));
rs.Close();
}

}
catch (Exception ex) { }
finally
{
fs.Close();
}

}

ftp = null;
//设置FTP命令
ftp = GetRequest(URI, username, password);
ftp.Method = System.Net.WebRequestMethods.Ftp.Rename; //改名
ftp.RenameTo = fileinfo.Name;
try
{
ftp.GetResponse();
}
catch (Exception ex)
{
ftp = GetRequest(URI, username, password);
ftp.Method = System.Net.WebRequestMethods.Ftp.DeleteFile; //删除
ftp.GetResponse();
throw ex;
}
finally
{
//fileinfo.Delete();
}

// 可以记录一个日志 "上传" + fileinfo.FullName + "上传到" + "FTP://" + hostname + "/" + targetDir + "/" + fileinfo.Name + "成功." );
ftp = null;

#region
/*****
*FtpWebResponse
* ****/
//FtpWebResponse ftpWebResponse = (FtpWebResponse)ftp.GetResponse();
#endregion
}

/// <summary>
/// 下载文件
/// </summary>
/// <param name="localDir">下载至本地路径</param>
/// <param name="FtpDir">ftp目标文件路径</param>
/// <param name="FtpFile">从ftp要下载的文件名</param>
/// <param name="hostname">ftp地址即IP</param>
/// <param name="username">ftp用户名</param>
/// <param name="password">ftp密码</param>
public static void DownloadFile(string localDir, string FtpDir, string FtpFile, string hostname, string username, string password)
{
string URI = "FTP://" + hostname + "/" + FtpDir + "/" + FtpFile;
string tmpname = Guid.NewGuid().ToString();
string localfile = localDir + @"\" + tmpname;

System.Net.FtpWebRequest ftp = GetRequest(URI, username, password);
ftp.Method = System.Net.WebRequestMethods.Ftp.DownloadFile;
ftp.UseBinary = true;
ftp.UsePassive = false;

using (FtpWebResponse response = (FtpWebResponse)ftp.GetResponse())
{
using (Stream responseStream = response.GetResponseStream())
{
//loop to read & write to file
using (FileStream fs = new FileStream(localfile, FileMode.CreateNew))
{
try
{
byte[] buffer = new byte[2048];
int read = 0;
do
{
read = responseStream.Read(buffer, 0, buffer.Length);
fs.Write(buffer, 0, read);
} while (!(read == 0));
responseStream.Close();
fs.Flush();
fs.Close();
}
catch (Exception)
{
//catch error and delete file only partially downloaded
fs.Close();
//delete target file as it's incomplete
File.Delete(localfile);
throw;
}
}

responseStream.Close();
}

response.Close();
}

try
{
File.Delete(localDir + @"\" + FtpFile);
File.Move(localfile, localDir + @"\" + FtpFile);

ftp = null;
ftp = GetRequest(URI, username, password);
ftp.Method = System.Net.WebRequestMethods.Ftp.DeleteFile;
ftp.GetResponse();

}
catch (Exception ex)
{
File.Delete(localfile);
throw ex;
}

// 记录日志 "从" + URI.ToString() + "下载到" + localDir + @"\" + FtpFile + "成功." );
ftp = null;
}

/// <summary>
/// 搜索远程文件
/// </summary>
/// <param name="targetDir"></param>
/// <param name="hostname"></param>
/// <param name="username"></param>
/// <param name="password"></param>
/// <param name="SearchPattern"></param>
/// <returns></returns>
public static List<string> ListDirectory(string targetDir, string hostname, string username, string password, string SearchPattern)
{
List<string> result = new List<string>();
try
{
string URI = "FTP://" + hostname + "/" + targetDir + "/" + SearchPattern;

System.Net.FtpWebRequest ftp = GetRequest(URI, username, password);
ftp.Method = System.Net.WebRequestMethods.Ftp.ListDirectory;
ftp.UsePassive = true;
ftp.UseBinary = true;

string str = GetStringResponse(ftp);
str = str.Replace("\r\n", "\r").TrimEnd('\r');
str = str.Replace("\n", "\r");
if (str != string.Empty)
result.AddRange(str.Split('\r'));

return result;
}
catch { }
return null;
}

private static string GetStringResponse(FtpWebRequest ftp)
{
//Get the result, streaming to a string
string result = "";
using (FtpWebResponse response = (FtpWebResponse)ftp.GetResponse())
{
long size = response.ContentLength;
using (Stream datastream = response.GetResponseStream())
{
using (StreamReader sr = new StreamReader(datastream, System.Text.Encoding.Default))
{
result = sr.ReadToEnd();
sr.Close();
}

datastream.Close();
}

response.Close();
}

return result;
}