C# 如何复制FTP服务器上的文件？

How to copy a file on an FTP server?

提问by msbg

How do you copy a file on an FTP server? My goal is to copy ftp://www.mysite.com/test.jpgto ftp://www.mysite.com/testcopy.jpg. To rename a file, I would use:

如何复制 FTP 服务器上的文件？我的目标是复制ftp://www.mysite.com/test.jpg到ftp://www.mysite.com/testcopy.jpg. 要重命名文件，我会使用：

var request = (FtpWebRequest)WebRequest.Create("ftp://www.mysite.com/test.jpg");
request.Credentials = new NetworkCredential(user, pass);
request.Method = WebRequestMethods.Ftp.Rename;
request.RenameTo = "testrename.jpg"
request.GetResponse().Close();

FtpWebResponse resp = (FtpWebResponse)request.GetResponse();

However, there is no Method for copying files. How would you do copy a file?

但是，没有复制文件的方法。你会如何复制文件？

采纳答案by Hanlet Esca?o

Try this:

尝试这个：

static void Main(string[] args)
{
    CopyFile("countrylist.csv", "MySample.csv", "username", "password#");
}

public static bool CopyFile(string fileName, string FileToCopy, string userName, string password)
{
    try
    {
        FtpWebRequest request = (FtpWebRequest)WebRequest.Create("ftp://ftp.mysite.net/" + fileName);
        request.Method = WebRequestMethods.Ftp.DownloadFile;

        request.Credentials = new NetworkCredential(userName, password);
        FtpWebResponse response = (FtpWebResponse)request.GetResponse();
        Stream responseStream = response.GetResponseStream();
        Upload("ftp://ftp.mysite.net/" + FileToCopy, ToByteArray(responseStream), userName, password);
        responseStream.Close();
        return true;
    }
    catch
    {
        return false;
    }
}

public static Byte[] ToByteArray(Stream stream)
{
    MemoryStream ms = new MemoryStream();
    byte[] chunk = new byte[4096];
    int bytesRead;
    while ((bytesRead = stream.Read(chunk, 0, chunk.Length)) > 0)
    {
        ms.Write(chunk, 0, bytesRead);
    }

    return ms.ToArray();
}

public static bool Upload(string FileName, byte[] Image, string FtpUsername, string FtpPassword)
{
    try
    {
        System.Net.FtpWebRequest clsRequest = (System.Net.FtpWebRequest)System.Net.WebRequest.Create(FileName);
        clsRequest.Credentials = new System.Net.NetworkCredential(FtpUsername, FtpPassword);
        clsRequest.Method = System.Net.WebRequestMethods.Ftp.UploadFile;
        System.IO.Stream clsStream = clsRequest.GetRequestStream();
        clsStream.Write(Image, 0, Image.Length);

        clsStream.Close();
        clsStream.Dispose();
        return true;
    }
    catch
    {
        return false;
    }
}

This downloads the file to a stream, and then uploads it.

这会将文件下载到流中，然后上传。

回答by Black Frog

FtpWebRequest is a lightweight class. Microsoft felt it should be used by simple client to download and delete the files once the client is finish.

FtpWebRequest 是一个轻量级的类。微软认为应该由简单的客户端使用它在客户端完成后下载和删除文件。

回答by msbg

I guess you can't really do this with FTP. What you can do is download the file you want to copy and then upload it with a new name. For example:

我想你真的不能用 FTP 来做到这一点。您可以做的是下载您要复制的文件，然后使用新名称上传它。例如：

        try
        {
            WebClient request = new WebClient();
            request.Credentials = new NetworkCredential(user, pass);
            byte[] data = request.DownloadData(host);
            MemoryStream file = new MemoryStream(data);
            Upload(data);
        }
        catch (Exception ex)
        {

        }

    ...

    private void Upload(byte[] buffer)
    {
        try
        {
            FtpWebRequest request = (FtpWebRequest)FtpWebRequest.Create(newname);

            request.Method = WebRequestMethods.Ftp.UploadFile;
            request.Credentials = new NetworkCredential(user, pass);

            Stream reqStream = request.GetRequestStream();
            reqStream.Write(buffer, 0, buffer.Length);
            reqStream.Close();

            var resp = (FtpWebResponse)request.GetResponse();
        }
        catch (Exception ex)
        {

        }
    }

回答by Yousuf Azad

In our project we did someting like this

在我们的项目中，我们做了这样的事情

// pass parameters according to your need, 
// the below code is done in a hard coded manner for clarity
public void Copy()  
{
    // from where you want to copy
    var downloadRequest = (FtpWebRequest)WebRequest.Create("ftp://www.mysite.com/test.jpg");
    downloadRequest.Credentials = new NetworkCredential("userName", "passWord");
    downloadRequest.Method = WebRequestMethods.Ftp.DownloadFile;

    var ftpWebResponse = (FtpWebResponse)downloadRequest.GetResponse();
    var downloadResponse = ftpWebResponse.GetResponseStream();

    int buffLength = 2048;
    byte[] byteBuffer = new byte[buffLength];

    // bytes read from download stream. 
    // from documentation: When overridden in a derived class, reads a sequence of bytes from the  
    // current stream and advances the position within the stream by the number of bytes read.
    int bytesRead = downloadResponse.Read(byteBuffer, 0, buffLength);

    // the place where you want the file to go
    var uploadRequest = (FtpWebRequest)WebRequest.Create("ftp://www.mysite.com/testCopy.jpg");
    uploadRequest.Credentials = new NetworkCredential("userName", "passWord");
    uploadRequest.Method = WebRequestMethods.Ftp.UploadFile;

    var uploadStream = uploadRequest.GetRequestStream();

    if (bytesRead > 0)
    {
        while (bytesRead > 0)
        {
            uploadStream.Write(byteBuffer, 0, bytesRead);
            bytesRead = downloadResponse.Read(byteBuffer, 0, buffLength);
        }
    }

    uploadStream.Close();
    uploadStream.Dispose();

    downloadResponse.Close();
    ftpWebResponse.Close();
    ((IDisposable)ftpWebResponse).Dispose();
}