The idea of my program is to allow the user to save his data in a cloud. The data is stored in binary serialized files.
Serialization Code looks like so:
FileStream Stream = new FileStream(..., FileMode.Create); // create stream
BinaryFormatter Formatter = new BinaryFormatter(); // create formatter
Formatter.Serialize(Stream, ObjectToSerialize); // serialize
Stream.Close();
The Problem is that when I upload the serialized file, with the following code:
FtpWebRequest Request = (FtpWebRequest)WebRequest.Create(new Uri(...));
Request.Method = WebRequestMethods.Ftp.UploadFile;
Request.Credentials = new NetworkCredential(..., ...);
string Path = System.IO.Path.GetDirectoryName(...;
StreamReader SourceStream = new StreamReader(Path);
Request.UseBinary = true;
byte[] FileContents = Encoding.Default.GetBytes(SourceStream.ReadToEnd());
SourceStream.Close();
Request.ContentLength = FileContents.Length;
Stream RequestStream = Request.GetRequestStream();
RequestStream.Write(FileContents, 0, FileContents.Length);
RequestStream.Close();
FtpWebResponse Response = (FtpWebResponse)Request.GetResponse();
Response.Close();
the file encoding changes (I am not sure about that.. if the encoding is the problem but I think so) and I am not able to deserialize the file anymore, exceptions occure. Do you have a idea how to do not damage the file?
Best Regards!
Encoding only applies to text, and you're dealing with a binary file here. You should not attempt to read it as a string. The "encoding changed" because you are using Encoding.Default which depends on the current configuration of your operating system.
Just change the code to:
string Path = System.IO.Path.GetDirectoryName(...);
// StreamReader SourceStream = new StreamReader(Path);
// Request.UseBinary = true;
byte[] FileContents = File.ReadAllBytes(Path);
// SourceStream.Close();
if you want to read an entire binary file in memory.
Related
I sended a WebRequest, and got as Response a String with XML Code within my content.
WebRequest request = WebRequest.Create("...");
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream dataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(dataStream);
string responseFromServer = reader.ReadToEnd();
byte[] bytes = Convert.FromBase64String(responseFromServer);
Image image;
using (MemoryStream ms = new MemoryStream(bytes))
{
image = Image.FromStream(ms);
}
image.Save("File", System.Drawing.Imaging.ImageFormat.Gif);
The Problem is that "Convert.FromBase64String(responseFromServer)" cant convert to base 64, because the response is:
"<string xmlns="*LINK*"> 'content' </string>"
Can I remove these Tags, or copy out the content?
I hope you got my problem:) Thanks for help and sorry for the bad english x)
you can use XmlDocument..
WebRequest request = WebRequest.Create("...");
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream dataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(dataStream);
XmlDocument doc = new XmlDocument();
doc.Load(reader);
byte[] bytes = Convert.FromBase64String(doc.GetElementsByTagName("string")[0].InnerText);
System.Drawing.Image image;
using (MemoryStream ms = new MemoryStream(bytes))
{
image = System.Drawing.Image.FromStream(ms);
}
I'd recommend using XmlReader for this.
WebRequest request = WebRequest.Create("...");
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream dataStream = response.GetResponseStream();
//StreamReader reader = new StreamReader(dataStream);
//string responseFromServer = reader.ReadToEnd();
//byte[] bytes = Convert.FromBase64String(responseFromServer);
using (var reader = XmlReader.Create(dataStream))
{
reader.Read();
reader.Read();
string base64 = reader.Value;
byte[] bytes = Convert.FromBase64String(base64);
Image image;
using (MemoryStream ms = new MemoryStream(bytes))
{
image = Image.FromStream(ms);
image.Save("File", System.Drawing.Imaging.ImageFormat.Gif);
}
}
There is a method for converting from Base64 in the element value directly, but you'd need to know things that more or less require you to read your whole stream anyway to do that (you can look at the edit history to see me working through that ;).
I am using FtpWebRequest to download files, but in all text files all \r\n are removed when downloaded.
What am I doing wrong?
Uri u = new Uri(msg);
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(u);
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.Credentials = credential;
request.UsePassive = true;
request.UseBinary = true;
request.KeepAlive = false;
//Get a reponse
WebResponse response = request.GetResponse();
Stream responseStream = response.GetResponseStream();
FileStream localfileStream = new FileStream(destination,
FileMode.Create, FileAccess.Write);
//create the file
byte[] buffer = new byte[1024];
int bytesRead = responseStream.Read(buffer, 0, 1024);
while (bytesRead != 0)
{
localfileStream.Write(buffer, 0, bytesRead);
bytesRead = responseStream.Read(buffer, 0, 1024);
}
localfileStream.Close();
response.Close();
responseStream.Close();.
Your code is correct. There is something else you are not telling that causing the problem. My guess would be
a) File on the server does not have \r\n
b) The way how you check that it does not have them on the client is wrong. Either you are checking a wrong file, or it had gone additional transformation or something else.
I've had a similar problem to this. The code I used is almost identical to yours. I found that the code for me was actually working correctly, but the file on the server only contained the the "LF" character at the end of the line, not the "CR/LF" combo. Most text editors ignore this, and display the text as one continuous line.
I have zip file in ftp server,this zip file contain more then one xml file in it,i want to download this zipfile and save to local disk,i have write below code,i download file but when i try to Extract this zip it throw me error that File is corrupted......
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(_remoteHost + file);
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.Credentials = new NetworkCredential(_remoteUser, _remotePass);
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
Stream responseStream = response.GetResponseStream();
StreamReader reader = new StreamReader(responseStream);
StreamWriter writer = new StreamWriter(destination);
writer.Write(reader.ReadToEnd());
writer.Close();
reader.Close();
response.Close();
You are channeling the result of the FTP request through a StreamReader. This has the usually beneficial effect of handling character encoding, but is not something you ever want to do when dealing with binary data (i.e. a zip file). Instead, you should read the data directly from the stream. Something like:
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(_remoteHost + file);
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.Credentials = new NetworkCredential(_remoteUser, _remotePass);
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
Stream responseStream = response.GetResponseStream();
// Copy the data from the responseStream to destination 1k at a time (feel free to increase buffer size)
byte[] buffer = new byte[1024];
for (int amountRead = responseStream.Read(buffer, 0, buffer.Length); amountRead > 0; amountRead = responseStream.Read(buffer, 0, buffer.Length))
{
destination.Write(buffer, 0, amountRead);
}
destination.Flush();
response.Close();
Here are sample code for Download file from FTP Server
Uri url = new Uri("ftp://ftp.demo.com/file1.txt");
if (url.Scheme == Uri.UriSchemeFtp)
{
FtpWebRequest objRequest = (FtpWebRequest)FtpWebRequest.Create(url);
//Set credentials if required else comment this Credential code
NetworkCredential objCredential = new NetworkCredential("FTPUserName", "FTPPassword");
objRequest.Credentials = objCredential;
objRequest.Method = WebRequestMethods.Ftp.DownloadFile;
FtpWebResponse objResponse = (FtpWebResponse)objRequest.GetResponse();
StreamReader objReader = new StreamReader(objResponse.GetResponseStream());
byte[] buffer = new byte[16 * 1024];
int len = 0;
FileStream objFS = new FileStream(Server.MapPath("file1.txt"), FileMode.Create, FileAccess.Write, FileShare.Read);
while ((len = objReader.BaseStream.Read(buffer, 0, buffer.Length)) != 0)
{
objFS.Write(buffer, 0, len);
}
objFS.Close();
objResponse.Close();
}
I think that your problem is the way that you download the zip, here's an article explaining how to use it, i hope it helps:
http://www.vcskicks.com/download-file-ftp.php
Also, there is a question like this here:
how to download compressed file (.zip) through FTP using c#?
I am trying to post data to server that accepts compressed data. The code below works just fine, but it is uncompressed. I have not worked with compression or Gzip beofre, so any help is appriciated.
HttpWebRequest request = WebRequest.Create(uri) as HttpWebRequest;
request.Timeout = 600000;
request.Method = verb; // POST
request.Accept = "text/xml";
if (!string.IsNullOrEmpty(data))
{
request.ContentType = "text/xml";
byte[] byteData = UTF8Encoding.UTF8.GetBytes(data);
request.ContentLength = byteData.Length;
// Here is where I need to compress the above byte array using GZipStream
using (Stream postStream = request.GetRequestStream())
{
postStream.Write(byteData, 0, byteData.Length);
}
}
XmlDocument xmlDoc = new XmlDocument();
HttpWebResponse response = null;
StreamReader reader = null;
try
{
response = request.GetResponse() as HttpWebResponse;
reader = new StreamReader(response.GetResponseStream());
xmlDoc.LoadXml(reader.ReadToEnd());
}
Do I gzip the entire byte array? Do I need to add other headers or remove the one that is already there?
Thanks!
-Scott
To answer the question you asked, to POST compressed data, all you need to do is wrap the request stream with a gzip stream
using (Stream postStream = request.GetRequestStream())
{
using(var zipStream = new GZipStream(postStream, CompressionMode.Compress))
{
zipStream.Write(byteData, 0, byteData.Length);
}
}
This is completely different than requesting a gzip response, which is a much more common thing to do.
I also received the "Cannot close stream until all bytes are written" error using code similar to tnyfst's. The problem was that I had:
request.ContentLength = binData.Length;
where binData is my raw data before the compression. Obviously the length of the compressed content would be different, so I just removed this line and ended up with this code:
using (GZipStream zipStream = new GZipStream(request.GetRequestStream(), CompressionMode.Compress))
{
zipStream.Write(binData, 0, binData.Length);
}
In Page_Load event:
Response.AddHeader("Content-Encoding", "gzip");
And for making compressed requests:
HttpWebRequest and GZip Http Responses by Rick Strahl
Try this extension method.
The stream will be left open (see the GZipStream constructor).
The stream position is set to 0 after the compression is done.
public static void GZip(this Stream stream, byte[] data)
{
using (var zipStream = new GZipStream(stream, CompressionMode.Compress, true))
{
zipStream.Write(data, 0, data.Length);
}
stream.Position = 0;
}
You can use the following test:
[Test]
public void Test_gzip_data_is_restored_to_the_original_value()
{
var stream = new MemoryStream();
var data = new byte[]{1,2,3,4,5,6,7,8,9,10};
stream.GZip(data);
var decompressed = new GZipStream(stream, CompressionMode.Decompress);
var data2 = new byte[10];
decompressed.Read(data2,0,10);
Assert.That(data, Is.EqualTo(data2));
}
For more information see: http://msdn.microsoft.com/en-us/library/hh158301(v=vs.110).aspx
I’m using the following code to download a file from a remote ftp server:
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(serverPath);
request.KeepAlive = true;
request.UsePassive = true;
request.UseBinary = true;
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.Credentials = new NetworkCredential(userName, password);
using (FtpWebResponse response = (FtpWebResponse)request.GetResponse())
using (Stream responseStream = response.GetResponseStream())
using (StreamReader reader = new StreamReader(responseStream))
using (StreamWriter destination = new StreamWriter(destinationFile))
{
destination.Write(reader.ReadToEnd());
destination.Flush();
}
The file that I’m downloading is a dll and my problem is that it is being altered by this process in some way. I know this because the file size is increasing. I have a suspicion that this section of code is at fault:
destination.Write(reader.ReadToEnd());
destination.Flush();
Can anyone offer any ideas as to what may be wrong?
StreamReader and StreamWriter work with character data, so you are decoding the stream from bytes to characters and then encoding it back to bytes again. A dll file contains binary data, so this round-trip conversion will introduce errors. You want to read bytes directly from the responseStream object and write to a FileStream that isn't wrapped in a StreamWriter.
If you are using .NET 4.0 you can use Stream.CopyTo, but otherwise you will have to copy the stream manually. This StackOverflow question has a good method for copying streams:
public static void CopyStream(Stream input, Stream output)
{
byte[] buffer = new byte[32768];
while (true)
{
int read = input.Read(buffer, 0, buffer.Length);
if (read <= 0)
return;
output.Write(buffer, 0, read);
}
}
So, your code will look like this:
using (FtpWebResponse response = (FtpWebResponse)request.GetResponse())
using (Stream responseStream = response.GetResponseStream())
using (FileStream destination = File.Create(destinationFile))
{
CopyStream(responseStream, destination);
}