使用C＃/ .NET在FTP服务器上传/下载二进制文件 [英] Upload and download a binary file to/from FTP server in C#/.NET

问题描述

我使用.NET 4 C＃。我试图上传，然后下载一个ZIP文件到我的服务器。

上传我有

<$ （WebClient客户端=新WebClient（））
{
FtpWebRequest请求=（FtpWebRequest）WebRequest.Create（MyUrl）; p $ p>
request.Method = WebRequestMethods.Ftp.UploadFile;
request.EnableSsl = false;
request.Credentials = new NetworkCredential（MyLogin，MyPassword）;
byte [] fileContents = null;
using（StreamReader sourceStream = new StreamReader（LocalFilePath））
{
fileContents = Encoding.UTF8.GetBytes（sourceStream.ReadToEnd（））;
}
request.ContentLength = fileContents.Length;
using（Stream requestStream = request.GetRequestStream（））
{
requestStream.Write（fileContents，0，fileContents.Length）;
}
FtpWebResponse response = null;
response =（FtpWebResponse）request.GetResponse（）;
response.Close（）;

$ / code>

这似乎起作用，因为我在服务器上得到一个文件正确的尺寸。



1）我如何进行流式处理，而不是先将它加载到内存中？我将上传非常大的文件。

并且为了下载我有

 使用（WebClient客户端=新的WebClient（））
 {
 string HtmlResult = String.Empty; 
 FtpWebRequest请求=（FtpWebRequest）WebRequest.Create（remoteFile）; 
 request.Method = WebRequestMethods.Ftp.DownloadFile; 
 request.EnableSsl = false; 
 request.Credentials = new NetworkCredential（MyLogin，MyPassword）; 
 using（FtpWebResponse response =（FtpWebResponse）request.GetResponse（））
 using（Stream responseStream = response.GetResponseStream（））
 using（StreamReader reader = new StreamReader（responseStream））
 using（FileStream writer = new FileStream（localFilename，FileMode.Create））
 {
 long length = response.ContentLength; 
 int bufferSize = 2048; 
 int readCount; 
 byte [] buffer = new byte [2048]; 
 readCount = responseStream.Read（buffer，0，bufferSize）; 
 while（readCount> 0）
 {
 writer.Write（buffer，0，readCount）; 
 readCount = responseStream.Read（buffer，0，bufferSize）; 
 
 
 
 
 
 $ 2 b）一切似乎都奏效...除非当我试图解压缩下载的ZIP文件时，我得到一个无效的ZIP文件。    
解决方案
 
上传
 
 
 
使用.NET框架将二进制文件上传到FTP服务器的最简单方法是使用  WebClient.UploadFile  ： 
 
 
  WebClient client = new WebClient（）; 
 client.Credentials = new NetworkCredential（username，password）; 
 client.UploadFile（ftp://ftp.example.com/remote/path/file.zip，@C：\local\path\file.zip）; 
  
如果您需要更大的控制权，那 WebClient 不提供（如TLS / SSL加密等），请使用 的FtpWebRequest  。简单的方法是使用 FileStream 复制到FTP流。 stream.copyto.aspxrel =nofollow noreferrer>  Stream.CopyTo  ： 
 
 
  FtpWebRequest请求= 
（FtpWebRequest）WebRequest.Create（ftp://ftp.example.com/remote/path/file.zip）; 
 request.Credentials = new NetworkCredential（username，password）; 
 request.Method = WebRequestMethods.Ftp.UploadFile;使用（Stream ftpStream = request.GetRequestStream（））获得
 
（Stream fileStream = File.OpenRead（@C：\local\path\file.zip））
 using 
 {
 fileStream.CopyTo（ftpStream）; 
 
 $ / code> 
如果您需要监控上传进度，您必须复制内容你自己： 
 
 
  FtpWebRequest请求= 
（FtpWebRequest）WebRequest.Create（ftp：//ftp.example。 COM /远程/路径/ file.zip）; 
 request.Credentials = new NetworkCredential（username，password）; 
 request.Method = WebRequestMethods.Ftp.UploadFile;使用（Stream ftpStream = request.GetRequestStream（））
使用（Stream fileStream = File.OpenRead（@C：\local\path\file.zip））
 
 {
 byte [] buffer = new byte [10240]; 
 int读取; 
 while（（read = fileStream.Read（buffer，0，buffer.Length））> 0）
 {
 ftpStream.Write（buffer，0，read）; 
 Console.WriteLine（上传的{0}字节，fileStream.Position）; 
 
 
 
 
 
 
 
对于GUI进度（WinForms  ProgressBar ），请参阅：
 
 如何显示上传进度条FtpWebRequest  
 
 
 
如果您想上传文件夹中的所有文件，请参阅
 
 使用WebClient上传文件目录。     下载 > 
 
 
使用.NET框架从FTP服务器下载二进制文件最简单的方法是使用 
 $ b>  $ b 
  WebClient client = new WebClient（）; 
 client.Credentials = new NetworkCredential（username，password）; 
 client.DownloadFile（
ftp://ftp.example.com/remote/path/file.zip，@C：\local\path\file.zip）; 
  
如果您需要更大的控制权，那 WebClient 不提供（如TLS / SSL加密等），请使用 的FtpWebRequest  。简单的方法是使用 FileStream  .stream.copyto.aspxrel =nofollow noreferrer>  Stream.CopyTo  ： 
 
 
  FtpWebRequest请求= 
（FtpWebRequest）WebRequest.Create（ftp://ftp.example.com/remote/path/file.zip）; 
 request.Credentials = new NetworkCredential（username，password）; 
 request.Method = WebRequestMethods.Ftp.DownloadFile;使用（Stream fileStream = File.Create（@C：\ local \\\\\\\\\\\' zip））
 {
 ftpStream.CopyTo（fileStream）; 
} 
  
如果您需要监视下载进度，则必须复制内容你自己： 
 
 
  FtpWebRequest请求= 
（FtpWebRequest）WebRequest.Create（ftp：//ftp.example。 COM /远程/路径/ file.zip）; 
 request.Credentials = new NetworkCredential（username，password）; 
 request.Method = WebRequestMethods.Ftp.DownloadFile;使用（Stream fileStream = File.Create（@C：\ local \\\\\\\\\\\' zip））
 {
 byte [] buffer = new byte [10240]; 
 int读取; （（read = ftpStream.Read（buffer，0，buffer.Length））> 0）
 {
 fileStream.Write（buffer，0，read）; 
 Console.WriteLine（已下载的{0}个字节，fileStream.Position）; 
 
 
 
 
 
 
 
对于GUI进度（WinForms  ProgressBar ），请参阅：
 
 使用ProgressBar进行FtpWebRequest FTP下载 
如果要从远程文件夹下载所有文件，请参阅
 
  C＃通过FTP下载所有文件和子目录。
 
I am using .NET 4 C#. I am trying to upload and then download a ZIP file to (my) server.

For uploading I have
using (WebClient client = new WebClient())
{
    FtpWebRequest request = (FtpWebRequest)WebRequest.Create(MyUrl);
    request.Method = WebRequestMethods.Ftp.UploadFile;
    request.EnableSsl = false;
    request.Credentials = new NetworkCredential(MyLogin, MyPassword);
    byte[] fileContents = null;
    using (StreamReader sourceStream = new StreamReader(LocalFilePath))
    {
        fileContents = Encoding.UTF8.GetBytes(sourceStream.ReadToEnd());
    }
    request.ContentLength = fileContents.Length;
    using (Stream requestStream = request.GetRequestStream())
    {
        requestStream.Write(fileContents, 0, fileContents.Length);
    }
    FtpWebResponse response = null;
    response = (FtpWebResponse)request.GetResponse();
    response.Close();
}
This seems to work, in that I get a file on the server of the right size.

1) How do I stream it, rather than load it into memory first?  I will be uploading very large files.

And for downloading I have
using (WebClient client = new WebClient())
{
    string HtmlResult = String.Empty;
    FtpWebRequest request = (FtpWebRequest)WebRequest.Create(remoteFile);
    request.Method = WebRequestMethods.Ftp.DownloadFile;
    request.EnableSsl = false;
    request.Credentials = new NetworkCredential(MyLogin, MyPassword);
    using (FtpWebResponse response = (FtpWebResponse)request.GetResponse())
    using (Stream responseStream = response.GetResponseStream())
    using (StreamReader reader = new StreamReader(responseStream))
    using (FileStream writer = new FileStream(localFilename, FileMode.Create))
    {
        long length = response.ContentLength;
        int bufferSize = 2048;
        int readCount;
        byte[] buffer = new byte[2048];
        readCount = responseStream.Read(buffer, 0, bufferSize);
        while (readCount > 0)
        {
            writer.Write(buffer, 0, readCount);
            readCount = responseStream.Read(buffer, 0, bufferSize);
        }
    }
}
2) Everything seems to work ... except when I try to unzip the downloaded ZIP file I get an invalid ZIP file.
解决方案
Upload

The most trivial way to upload a binary file to an FTP server using .NET framework is using WebClient.UploadFile:
WebClient client = new WebClient();
client.Credentials = new NetworkCredential("username", "password");
client.UploadFile("ftp://ftp.example.com/remote/path/file.zip", @"C:\local\path\file.zip");
If you need a greater control, that WebClient does not offer (like TLS/SSL encryption, etc), use FtpWebRequest. Easy way is to just copy a FileStream to FTP stream using Stream.CopyTo:
FtpWebRequest request =
    (FtpWebRequest)WebRequest.Create("ftp://ftp.example.com/remote/path/file.zip");
request.Credentials = new NetworkCredential("username", "password");
request.Method = WebRequestMethods.Ftp.UploadFile;  

using (Stream fileStream = File.OpenRead(@"C:\local\path\file.zip"))
using (Stream ftpStream = request.GetRequestStream())
{
    fileStream.CopyTo(ftpStream);
}
If you need to monitor an upload progress, you have to copy the contents by chunks yourself:
FtpWebRequest request =
    (FtpWebRequest)WebRequest.Create("ftp://ftp.example.com/remote/path/file.zip");
request.Credentials = new NetworkCredential("username", "password");
request.Method = WebRequestMethods.Ftp.UploadFile;  

using (Stream fileStream = File.OpenRead(@"C:\local\path\file.zip"))
using (Stream ftpStream = request.GetRequestStream())
{
    byte[] buffer = new byte[10240];
    int read;
    while ((read = fileStream.Read(buffer, 0, buffer.Length)) > 0)
    {
        ftpStream.Write(buffer, 0, read);
        Console.WriteLine("Uploaded {0} bytes", fileStream.Position);
    } 
}
For GUI progress (WinForms ProgressBar), see:

How can we show progress bar for upload with FtpWebRequest

If you want to upload all files from a folder, see

Upload directory of files using WebClient.



Download

The most trivial way to download a binary file from an FTP server using .NET framework is using WebClient.DownloadFile:
WebClient client = new WebClient();
client.Credentials = new NetworkCredential("username", "password");
client.DownloadFile(
    "ftp://ftp.example.com/remote/path/file.zip", @"C:\local\path\file.zip");
If you need a greater control, that WebClient does not offer (like TLS/SSL encryption, etc), use FtpWebRequest. Easy way is to just copy an FTP response stream to FileStream using Stream.CopyTo:
FtpWebRequest request =
    (FtpWebRequest)WebRequest.Create("ftp://ftp.example.com/remote/path/file.zip");
request.Credentials = new NetworkCredential("username", "password");
request.Method = WebRequestMethods.Ftp.DownloadFile;

using (Stream ftpStream = request.GetResponse().GetResponseStream())
using (Stream fileStream = File.Create(@"C:\local\path\file.zip"))
{
    ftpStream.CopyTo(fileStream);
}
If you need to monitor a download progress, you have to copy the contents by chunks yourself:
FtpWebRequest request =
    (FtpWebRequest)WebRequest.Create("ftp://ftp.example.com/remote/path/file.zip");
request.Credentials = new NetworkCredential("username", "password");
request.Method = WebRequestMethods.Ftp.DownloadFile;

using (Stream ftpStream = request.GetResponse().GetResponseStream())
using (Stream fileStream = File.Create(@"C:\local\path\file.zip"))
{
    byte[] buffer = new byte[10240];
    int read;
    while ((read = ftpStream.Read(buffer, 0, buffer.Length)) > 0)
    {
        fileStream.Write(buffer, 0, read);
        Console.WriteLine("Downloaded {0} bytes", fileStream.Position);
    }
}
For GUI progress (WinForms ProgressBar), see:

FtpWebRequest FTP download with ProgressBar

If you want to download all files from a remote folder, see

C# Download all files and subdirectories through FTP.

                        
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