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Image upload to FTP issue

I am using the following code to upload a image to my FTP server but I have a problem. If I use the code to check the dimension (height and width) of the image before upload then there is .png file created in the FTP server but it's empty (or invalid format) and if I remove the code to check the dimension, then the image is uploaded correctly. Does any have any idea on this?
public ActionResult UploadFile(int type, HttpPostedFileBase imagefile)
{
//check image height and width
using (System.Drawing.Image image = System.Drawing.Image.FromStream(imagefile.InputStream, true, true))
{
if (image.Width > 160 || image.Height > 160)
{
//do something here
}
}//end check image height and width
FtpWebRequest request = (FtpWebRequest)WebRequest.Create("ftpPath" + "/" + imagefile.FileName);
request.Credentials = new NetworkCredential("ftpUserName", "ftpPassword");
request.Method = WebRequestMethods.Ftp.UploadFile;
var sourceStream = imagefile.InputStream;
Stream requestStream = request.GetRequestStream();
request.ContentLength = sourceStream.Length;
int BUFFER_SIZE = imagefile.ContentLength;
byte[] buffer = new byte[BUFFER_SIZE];
int bytesRead = sourceStream.Read(buffer, 0, BUFFER_SIZE);
do
{
requestStream.Write(buffer, 0, bytesRead);
bytesRead = sourceStream.Read(buffer, 0, BUFFER_SIZE);
} while (bytesRead > 0);
sourceStream.Close();
requestStream.Close();
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
response.Close();
}

As mentioned, you are reading up all the stream when you load it into your Image. However, I don't think you can reset the position (i.e. "Seek") on a NetworkStream (your InputStream). Once you read it, it is gone.
One thing you can do though is to create a MemoryStream and use Stream.CopyTo to copy the contents into that. Then, you can do anything you like with it, including resetting the position to 0 to "read it a second time".
//example of resetting a stream named "s"
s.Position = 0;

Thanks guys for the reply they were very helpful but I fixed this issue by making slight changes on my code as below, I checked the image dimension after reading the input Stream. May be someone find this helpful.
public string ftpUpload(HttpPostedFileBase imagefile, string filename)
{
var sourceStream = imagefile.InputStream;
int BUFFER_SIZE = imagefile.ContentLength;
byte[] buffer = new byte[BUFFER_SIZE];
int bytesRead = sourceStream.Read(buffer, 0, BUFFER_SIZE);
if (!CheckLogoDimension(sourceStream))
{
sourceStream.Close();
return "error";
}
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(ftpRootPath + "/" + filename);
request.Credentials = new NetworkCredential(ftpUserName, ftpPassword);
request.Method = WebRequestMethods.Ftp.UploadFile;
Stream requestStream = request.GetRequestStream();
request.ContentLength = sourceStream.Length;
do
{
requestStream.Write(buffer, 0, bytesRead);
bytesRead = sourceStream.Read(buffer, 0, BUFFER_SIZE);
} while (bytesRead > 0);
sourceStream.Close();
requestStream.Close();
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
response.Close();
return "Success";
}

Stream to string

How do I append Stream output to a string instead of a file in this code?
HttpWebResponse res = (HttpWebResponse)httpRequest.GetResponse();
using (Stream output = File.OpenWrite(#"c:\temp\tmp.html"))
using (Stream input = res.GetResponseStream())
{
byte[] buffer = new byte[8192];
int bytesRead;
while ((bytesRead = input.Read(buffer, 0, buffer.Length)) > 0)
{
output.Write(buffer, 0, bytesRead);
}
input.Close();
output.Close();
}

You can use StreamReader:
HttpWebResponse res = (HttpWebResponse)httpRequest.GetResponse();
using (Stream input = res.GetResponseStream())
using (var streamReader = new StreamReader(input))
{
string result = streamReader.ReadToEnd();
}
Note this would read the entire string into memory.

Use encoding to get a string and then use StringReader to read buffer.
HttpWebResponse res = (HttpWebResponse)httpRequest.GetResponse();
using (Stream output = File.OpenWrite(#"c:\temp\tmp.html"))
using (Stream input = res.GetResponseStream())
{
byte[] buffer = new byte[8192];
int bytesRead;
while ((bytesRead = input.Read(buffer, 0, buffer.Length)) > 0)
{
output.Write(buffer, 0, bytesRead);
}
input.Close();
output.Close();
string sBuffer = Encoding.UTF8.GetString(buffer);
StringReader reader = new StringReader(sBuffer);
​

Changing FileStream Write encoding type

This is my code :
public static string DownloadFile(string FtpUrl, string FileNameToDownload,
string userName, string password, string tempDirPath)
{
string ResponseDescription = "";
string PureFileName = new FileInfo(FileNameToDownload).Name;
string DownloadedFilePath = tempDirPath + "/" + PureFileName;
string downloadUrl = String.Format("{0}/{1}", FtpUrl, FileNameToDownload);
FtpWebRequest req = (FtpWebRequest)FtpWebRequest.Create(downloadUrl);
req.Method = WebRequestMethods.Ftp.DownloadFile;
req.Credentials = new NetworkCredential(userName, password);
req.UseBinary = true;
req.Proxy = null;
try
{
FtpWebResponse response = (FtpWebResponse)req.GetResponse();
Stream stream = response.GetResponseStream();
byte[] buffer = new byte[2048];
FileStream fs = new FileStream(DownloadedFilePath, FileMode.Create);
int ReadCount = stream.Read(buffer, 0, buffer.Length);
while (ReadCount > 0)
{
fs.Write(buffer, 0, ReadCount);
ReadCount = stream.Read(buffer, 0, buffer.Length);
}
ResponseDescription = response.StatusDescription;
fs.Close();
stream.Close();
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
return ResponseDescription;
}
}
This code Downloads a file from a ftp server and write it to a specific path in server.
but the encoding of the saved file is not UTF-8.
I want to change the encoding type of the file to UTF-8.
Do I must use StreamReader ?
How Can I modify that code?

In theory, the below should work, but it depends or whether the responsestream can work together with the streamreader.
Writing with a different encoding is easy, you can simply use a streamwriter (based on textwriter) instead of a filestream. However, you can't write the bytes directly, since you have to write the properly formatted text. For that, the bytes have to be converted to text (Char buffer) with the proper original encoding.
char[] buffer = new char[2048]; //or 1024 if you want to keep the same block size
using (var reader = new StreamReader(stream, Encoding.Unicode)) // <= Or whatever encoding the orignal is
{
using (var tw = new StreamWriter(DownloadedFilePath, false, Encoding.UTF8)) //streamwriter instead of filestream
{
while (true)
{
int ReadCount = reader.Read(buffer, 0, buffer.Length);
if (ReadCount == 0) break;
tw.Write(buffer, 0, ReadCount);
}
ResponseDescription = response.StatusDescription;
stream.Close();
tw.Close();
}
}
If the streamreader gives problems, you can also download the bytes first, and use a streamreader on the already downloaded bytes.

You can wrap it in StreaWriter:
try
{
FtpWebResponse response = (FtpWebResponse)req.GetResponse();
Stream stream = response.GetResponseStream();
byte[] buffer = new byte[2048];
var sw = new StreamWriter( new FileStream(DownloadedFilePath, FileMode.Create),
Encoding.UTF8);
int ReadCount = stream.Read(buffer, 0, buffer.Length);
while (ReadCount > 0)
{
sw.Write(buffer, 0, ReadCount);
ReadCount = stream.Read(buffer, 0, buffer.Length);
}
ResponseDescription = response.StatusDescription;
sw.Close();
stream.Close();
}
I hope it will help
You have a look here :https://stackoverflow.com/ answer

File download For Current Request

I need to download the file as http response for the current http request.
Until now I used code as
System.Uri uri = System.Web.HttpContext.Current.Request.Url;
HttpWebRequest httpRequest = (HttpWebRequest)WebRequest.Create(
Path.Combine(uri.ToString(), filename));
httpRequest.Method = "GET";
using (HttpWebResponse httpResponse = (HttpWebResponse)httpRequest.GetResponse())
{
using (Stream responseStream = httpResponse.GetResponseStream())
{
using (FileStream localFileStream = new FileStream(
Path.Combine(localFolder, filename), FileMode.Open))
{
int bytesRead;
while ((bytesRead = responseStream.Read(buffer, 0, buffer.Length)) > 0)
{
totalBytesRead += bytesRead;
localFileStream.Write(buffer, 0, bytesRead);
}
}
}
}
But this code the request is only sending but not getting any responses...
Is this possible?

You should get the file off disk then use the Response.OutputStream to write the file directly to the response. Make sure to set the correct content headers so the browser will know what is coming.
FileInfo file = new FileInfo(Path.Combine(localFolder, filename));
int len = (int)file.Length, bytes;
Response.ContentType = "text/plain"; //Set the file type here
Response.AddHeader "Content-Disposition", "attachment;filename=" + filename;
context.Response.AppendHeader("content-length", len.ToString());
byte[] buffer = new byte[1024];
using(Stream stream = File.OpenRead(path)) {
while (len > 0 && (bytes =
stream.Read(buffer, 0, buffer.Length)) > 0)
{
Response.OutputStream.Write(buffer, 0, bytes);
len -= bytes;
}
}

Not sure, but it looks like your making a web request, getting the response stream, then attempting to buffer it out to localFolder. If so, FileMode.Open looks suspect ("should open an existing file..."?). Maybe use FileMode.Create.
MSDN ref
Also, does your web app needs to have write permissions to localFolder.

Read Http Request into Byte array

I'm developing a web page that needs to take an HTTP Post Request and read it into a byte array for further processing. I'm kind of stuck on how to do this, and I'm stumped on what is the best way to accomplish. Here is my code so far:
public override void ProcessRequest(HttpContext curContext)
{
if (curContext != null)
{
int totalBytes = curContext.Request.TotalBytes;
string encoding = curContext.Request.ContentEncoding.ToString();
int reqLength = curContext.Request.ContentLength;
long inputLength = curContext.Request.InputStream.Length;
Stream str = curContext.Request.InputStream;
}
}
I'm checking the length of the request and its total bytes which equals 128. Now do I just need to use a Stream object to get it into byte[] format? Am I going in the right direction? Not sure how to proceed. Any advice would be great. I need to get the entire HTTP request into byte[] field.
Thanks!

The simplest way is to copy it to a MemoryStream - then call ToArray if you need to.
If you're using .NET 4, that's really easy:
MemoryStream ms = new MemoryStream();
curContext.Request.InputStream.CopyTo(ms);
// If you need it...
byte[] data = ms.ToArray();
EDIT: If you're not using .NET 4, you can create your own implementation of CopyTo. Here's a version which acts as an extension method:
public static void CopyTo(this Stream source, Stream destination)
{
// TODO: Argument validation
byte[] buffer = new byte[16384]; // For example...
int bytesRead;
while ((bytesRead = source.Read(buffer, 0, buffer.Length)) > 0)
{
destination.Write(buffer, 0, bytesRead);
}
}

You can just use WebClient for that...
WebClient c = new WebClient();
byte [] responseData = c.DownloadData(..)
Where .. is the URL address for the data.

I use MemoryStream and Response.GetResponseStream().CopyTo(stream)
HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create(url);
myRequest.Method = "GET";
WebResponse myResponse = myRequest.GetResponse();
MemoryStream ms = new MemoryStream();
myResponse.GetResponseStream().CopyTo(ms);
byte[] data = ms.ToArray();

I have a function that does it, by sending in the response stream:
private byte[] ReadFully(Stream input)
{
try
{
int bytesBuffer = 1024;
byte[] buffer = new byte[bytesBuffer];
using (MemoryStream ms = new MemoryStream())
{
int readBytes;
while ((readBytes = input.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, readBytes);
}
return ms.ToArray();
}
}
catch (Exception ex)
{
// Exception handling here: Response.Write("Ex.: " + ex.Message);
}
}
Since you have Stream str = curContext.Request.InputStream;, you could then just do:
byte[] bytes = ReadFully(str);
If you had done this:
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(someUri);
req.Credentials = CredentialCache.DefaultCredentials;
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
You would call it this way:
byte[] bytes = ReadFully(resp.GetResponseStream());

class WebFetch
{
static void Main(string[] args)
{
// used to build entire input
StringBuilder sb = new StringBuilder();
// used on each read operation
byte[] buf = new byte[8192];
// prepare the web page we will be asking for
HttpWebRequest request = (HttpWebRequest)
WebRequest.Create(#"http://www.google.com/search?q=google");
// execute the request
HttpWebResponse response = (HttpWebResponse)
request.GetResponse();
// we will read data via the response stream
Stream resStream = response.GetResponseStream();
string tempString = null;
int count = 0;
do
{
// fill the buffer with data
count = resStream.Read(buf, 0, buf.Length);
// make sure we read some data
if (count != 0)
{
// translate from bytes to ASCII text
tempString = Encoding.ASCII.GetString(buf, 0, count);
// continue building the string
sb.Append(tempString);
}
}
while (count > 0); // any more data to read?
// print out page source
Console.WriteLine(sb.ToString());
Console.Read();
}
}

For all those cases when your context.Request.ContentLength is greather than zero, you can simply do:
byte[] contentBytes = context.Request.BinaryRead(context.Request.ContentLength);