I have the following code, which essentially reads an HTTP Response into a byte array and uses unsafe operations to copy data from the byte buffer into a specified region of a memory mapped file:
private static readonly ArrayPool<byte> Pool = ArrayPool<byte>.Shared;
[Obsolete("Obsolete")]
private static async Task GetStream(string url, long start, long end, MemoryMappedFile mmf, int bufferSize, CancellationToken cancellationToken)
{
var r = (HttpWebRequest)WebRequest.Create(url);
r.Method = "GET";
r.AddRange(start,end);
r.Pipelined = true;
r.KeepAlive = true;
using var response = await r.GetResponseAsync().ConfigureAwait(false);
var buffer = Pool.Rent(bufferSize);
try
{
await using var stream = response.GetResponseStream();
var accessor = mmf.CreateViewAccessor(start, response.ContentLength, MemoryMappedFileAccess.ReadWrite);
var bytesRead = 0;
var brtot = 0;
var total = 0;
int i = -1;
do
{
Array.Clear(buffer);
var offset = 0;
do {
bytesRead = await stream.ReadAsync(buffer, offset, bufferSize - offset, cancellationToken).ConfigureAwait(false);
brtot += bytesRead;
offset += bytesRead;
} while (bytesRead != 0 && offset < bufferSize);
if (offset == 0) {continue;}
i = i + 1;
if (brtot - total > 1)
{
CopyBytes(buffer, total, accessor, i == 0 ? brtot : brtot - total);
Console.WriteLine(String.Format("{0} - {1} ==== {2}", total, brtot - bytesRead, i));
total = brtot + 1;
}
} while (bytesRead != 0);
await stream.FlushAsync(cancellationToken);
}
finally
{
Pool.Return(buffer);
response.Close();
}
}
private static void CopyBytes(byte[] buff, int offset, MemoryMappedViewAccessor s, int length)
{
unsafe
{
var pointer = (byte*)0;
RuntimeHelpers.PrepareConstrainedRegions();
try {
s.SafeMemoryMappedViewHandle.AcquirePointer(ref pointer);
Marshal.Copy(buff, 0, IntPtr.Add(new IntPtr(pointer), offset), length);
}
finally {
if (pointer != null)
s.SafeMemoryMappedViewHandle.ReleasePointer();
}
}
}
Then I have this code that calls it:
public static async Task DownloadFile(string url, String outFile, int parts, int bufferSize)
{
var responseLength = (await WebRequest.Create(url).GetResponseAsync()).ContentLength;
var partSize = (long)Math.Floor(responseLength / (parts + 0.0));
var pieces = new List<ValueTuple<long, long>>();
var uri = new Uri(url);
var filename = outFile ?? Path.GetFileName(uri.LocalPath);
Console.WriteLine(responseLength);
Console.WriteLine(partSize);
ServicePointManager.Expect100Continue = false;
ServicePointManager.DefaultConnectionLimit = 10000;
ServicePointManager.FindServicePoint(new Uri(url)).ConnectionLimit = parts;
#if NET6_0_OR_GREATER
ServicePointManager.ReusePort = true;
#endif
//Loop to add all the events to the queue
for (long i = 0; i < responseLength; i += partSize) {
pieces.Insert(0,(i + partSize < responseLength ? new ValueTuple<long, long>(i, i + partSize) : new ValueTuple<long, long>(i, responseLength)));
}
var cs = new CancellationToken(false);
File.Delete(filename);
var mmf = MemoryMappedFile.CreateFromFile(filename, FileMode.CreateNew,null, responseLength, MemoryMappedFileAccess.ReadWrite);
GCSettings.LatencyMode = GCLatencyMode.SustainedLowLatency;
await Parallel.ForEachAsync(pieces, new ParallelOptions() { MaxDegreeOfParallelism = Environment.ProcessorCount}, async (tuple, token) =>
{
await GetStream(url,tuple.Item1, tuple.Item2, mmf, bufferSize, cs);
});
}
The only issue with the code is that it is corrupting whatever file I download with no errors. I am sure this is due to my parameters specified to CopyBytes(). But unfortunately, I can't get the right calculations for the parameters, can someone help me with this or at least point me on the right direction? I know some of the methods are obsolete, and I will address this, but I am currently more focused on getting the unsafe memory copying to work. Thank you!
I have been experiencing some issues with imcompatiabilities between the difference implementations of zlib compression.
As a test case I thought to create test data with 10000 doubles ranging from 0 - 10000.
I created some test code to compress and decompress this data that uses the compress and uncompress in zlib.c
unsigned int Test(char* comparisonFile)
{
unsigned long partsSize = 0x80000;
const int arraySize = 10000;
Bytef doubleArray[sizeof(double) * arraySize];
Bytef outBuffer[sizeof(double) * arraySize];
for (int i = 0; i < arraySize; i++)
{
Bytef doubleBytes[sizeof(double)];
*(double*)(doubleBytes) = (double)i;
for (int x = 0; x < 8; x++)
doubleArray[(8 * i) + x] = doubleBytes[x];
}
compress(outBuffer, &partsSize, doubleArray, sizeof(double) * arraySize);
//create file of compressed data
char * filename = "zlibCompressed";
FILE * file = fopen(filename, "w+b");
int compressResult = et_int64(fwrite((char *)outBuffer, 1, size_t(partsSize), file));
fclose(file);
//load file of compressed data either from zlib or other
if (comparisonFile != NULL)
filename = comparisonFile;
FILE * compressedFile = fopen(filename, "r+b");
if (compressedFile == NULL)
return -1;
unsigned long outBufferSize = sizeof(double) * arraySize;
fseek(compressedFile, 0, SEEK_END);
long fsize = ftell(compressedFile);
fseek(compressedFile, 0, SEEK_SET); /* same as rewind(f); */
partsSize = int(fsize);
double * doubleResult = new double [arraySize];
Bytef* inBuffer = (Bytef*)malloc(sizeof(Bytef)*partsSize);
int readresult = et_int64(fread((char *)inBuffer, 1, partsSize , compressedFile));
if (readresult != partsSize)
return -1;
Bytef * uncompressedOutBuffer = static_cast<Bytef*>((void *)doubleResult);
int result = uncompress(uncompressedOutBuffer, &outBufferSize, inBuffer, partsSize);
for (int i = 0; i < arraySize; i++)
{
// uncompressed data does not match expectation
if ((int)doubleResult[i] != i)
return -2;
}
fclose(compressedFile);
return 0;
}
This allows me to test the internal compression and also substitute compression results from C#.
However, when I use ionic or standard deflate in the following manner I can only recover about 8150 of the expected 10000.
The uncompression returns a:
Z_DATA_ERROR
Given that these seem in theory interoperable, i'm not sure why C# compression results can only be partially unpacked with Adler's zlib? Any help out there?
public void ZlibTest()
{
byte[] buffer;
using (var ms = new MemoryStream())
{
for (int i = 0; i < 10000; i++)
ms.Write(BitConverter.GetBytes((double) i), 0, sizeof(double));
buffer = ms.ToArray();
}
var file = "dummy1";
if (File.Exists(file))
File.Delete(file);
using (Stream fs = new FileStream(file, FileMode.OpenOrCreate, FileAccess.ReadWrite))
{
using (var resultStream = new MemoryStream())
{
using (var compressionStream2 = new Ionic.Zlib.ZlibStream(resultStream, Ionic.Zlib.CompressionMode.Compress, CompressionLevel.Default))
{
compressionStream2.Write(buffer, 0, buffer.Length);
var packetLength = (int)resultStream.Length;
fs.Write(resultStream.ToArray(), 0, packetLength);
}
}
}
file = "dummy2";
using (Stream fs = new FileStream(file, FileMode.OpenOrCreate, FileAccess.ReadWrite))
{
using (var resultStream = new MemoryStream())
{
using (var compressionStream2 = new System.IO.Compression.DeflateStream(resultStream, System.IO.Compression.CompressionMode.Compress))
{
compressionStream2.Write(buffer, 0, buffer.Length);
var packetLength = (int)resultStream.Length;
fs.Write(BitConverter.GetBytes((ushort)40056), 0, sizeof(ushort));
fs.Write(resultStream.ToArray(), 0, packetLength);
}
}
}
}
They're both using the same zlib. There must be an error in your C# code. It is possible that you are not reading the file in binary mode in C#, which would cause occasional corruption.
I want to add echo to wave file, in order to do so I need to open it and then save it first. I've written some methods but output file is not correct.
Testing input file size: 731 014
Output file sieze: 730 898
But the "space on disc" is the same for both files, which is 733 184
Error code or whatever it is displayed when opened: 0xc00d36c4
What can be the issue here? This looks pretty simple and yet it's not working. Here's my header, read and write methods:
class WaveFile
{
struct WaveHeader
{
public byte[] RiffID;
public uint fileSize;
public byte[] format;
//Wave format chunk 1
public byte[] fmtID;
public uint fmtSize;
public ushort audioFormat;
public ushort channels;
public uint sampleRate;
public uint byteRate;
public ushort blockAlign;
public int bitsPerSample;
//Wave format chunk 2
public byte[] dataID;
public uint dataSize;
}
uint samples;
public List<short> L;
public List<short> R;
WaveHeader header = new WaveHeader();
//loading file, preparation for modyfying
public bool loadWaveFile(string filePath)
{
using (FileStream fs = File.Open(filePath, FileMode.Open))
using (BinaryReader reader = new BinaryReader(fs))
{
// chunk 0
header.RiffID = reader.ReadBytes(4);
header.fileSize = reader.ReadUInt32();
header.format = reader.ReadBytes(4);
// chunk 1
header.fmtID = reader.ReadBytes(4);
header.fmtSize = reader.ReadUInt32();
header.audioFormat = reader.ReadUInt16();
header.channels = reader.ReadUInt16();
header.sampleRate = reader.ReadUInt32();
header.byteRate = reader.ReadUInt32();
header.blockAlign = reader.ReadUInt16();
header.bitsPerSample = reader.ReadInt16();
// chunk 2
header.dataID = reader.ReadBytes(4);
header.dataSize = reader.ReadUInt32();
// DATA is stereo
L = new List<short>();
R = new List<short>();
samples = header.dataSize / header.blockAlign;
for (int i = 0; i < samples; i++)
{
L.Add((short)reader.ReadUInt16());
R.Add((short)reader.ReadUInt16());
}
reader.Close();
fs.Close();
}
return true;
}
public bool addEcho(int threadsNumber, int echoesNumber, int delay, int attenuation)
{
return true;
}
public bool saveWaveFile(string savingPath)
{
using (FileStream fs = new FileStream(#savingPath + "\\echo.wav", FileMode.Create))
using (BinaryWriter writer = new BinaryWriter(fs))
{
//chunk 0
writer.Write(header.RiffID);
writer.Write(header.fileSize);
writer.Write(header.format);
//chunk 1
writer.Write(header.fmtID);
writer.Write(header.fmtSize);
writer.Write(header.audioFormat);
writer.Write(header.channels);
writer.Write(header.sampleRate);
writer.Write(header.byteRate);
writer.Write(header.blockAlign);
writer.Write(header.bitsPerSample);
//chunk 2
writer.Write(header.dataID);
writer.Write(header.dataSize);
for (int i = 0; i < samples; i++)
{
writer.Write(L[i]);
writer.Write(R[i]);
}
writer.Close();
fs.Close();
return true;
}
}
}
I didn't find out what the issue was, but for echo purposes this class will work:
Class WaveFile
{
byte[] byteArray;
public void loadWaveFile(string filePath)
{
byteArray = File.ReadAllBytes(filePath);
}
public bool addEcho(int threadsNumber, int echoesNumber, int delay, int attenuation)
{
return true;
}
public bool saveWaveFile(string savingPath)
{
using (FileStream fs = new FileStream(#savingPath + "\\echo.wav", FileMode.Create))
using (BinaryWriter writer = new BinaryWriter(fs))
{
writer.Write(byteArray);
writer.Close();
fs.Close();
return true;
}
}
}
I have a class to help me to play mp3 files from URL sources. It works good when playing, pausing and resuming. But I am confused about to fast-forward or backward.
I am using temporary files to store mp3 data and I want to re-position the FileStream according to position the user selected. But there is a problem for it.
Problem: If the position doesn't exist yet. (Not downloaded yet)
This can be solved using WebRequest.AddRange() but in this case, we have to open a new FileStream to store bytes separately and calling AddRange() method every time that user wants to go forward or backward means that the file is going to be re-downloaded from that position. However, if this is done too often, we have to download the file as many as the number of the forward or backward.
So, if there is a simple and quota-friendly solution please let me know it. I can't figure out how to do it. Help please!
My code:
public class NAudioPlayer
{
HttpWebRequest req;
HttpWebResponse resp;
Stream stream;
WaveOut waveOut;
Mp3WaveFormat format;
AcmMp3FrameDecompressor decompressor;
BufferedWaveProvider provider;
FileStream tempFileStream;
System.Windows.Forms.Timer ticker;
private int bufferedDuration;
string url, path;
long size, streamPos;
int timeOffset, timePosition, avgBytes, duration;
bool formatKnown, waitinloop, exitloop;
State currentState;
public NAudioPlayer(string mp3Url)
{
this.url = mp3Url;
this.currentState = State.Stopped;
this.size = -1;
this.timeOffset = 0;
this.timePosition = 0;
this.avgBytes = 0;
this.duration = 0;
this.format = null;
this.ticker = new System.Windows.Forms.Timer();
this.waveOut = new WaveOut();
this.waitinloop = false;
ticker.Interval = 250;
ticker.Tick += ticker_Tick;
}
int target = 0;
void ticker_Tick(object sender, EventArgs e)
{
if (waveOut.PlaybackState == PlaybackState.Playing)
{
timePosition = timeOffset + (int)(waveOut.GetPosition() * 1d / waveOut.OutputWaveFormat.AverageBytesPerSecond);
Debug.WriteLine(timePosition);
}
if (duration != 0 && timePosition >= duration)
{
waveOut.Stop();
ticker.Stop();
}
if (timePosition == target && timePosition < duration - 5 &&
provider != null && provider.BufferedDuration.TotalSeconds < 5)
{
waveOut.Pause();
currentState = State.Buffering;
target = timePosition + 5;
}
if (currentState == State.Buffering && provider != null && provider.BufferedDuration.TotalSeconds >= 5)
{
waveOut.Play();
}
}
public void Play()
{
int range = avgBytes <= 0 ? 0 : timeOffset * avgBytes;
int readBytes = 0;
long pos = 0;
this.streamPos = 0;
exitloop = false;
disposeAllResources();
ticker.Start();
Task.Run(() =>
{
//Crate WebRequest using AddRange to enable repositioning the mp3
req = WebRequest.Create(url) as HttpWebRequest;
req.AllowAutoRedirect = true;
req.ServicePoint.ConnectionLimit = 100;
req.UserAgent = "Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Firefox/31.0";
req.AddRange(range);
resp = req.GetResponse() as HttpWebResponse;
stream = resp.GetResponseStream();
size = resp.ContentLength;
//Create a unique file to store data
path = Path.GetTempPath() + Guid.NewGuid().ToString() + ".mp3";
tempFileStream = new FileStream(path, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite);
waveOut.Stop();
waveOut = new WaveOut();
if (provider != null)
waveOut.Init(provider);
byte[] buffer = new byte[17 * 1024];
while ((readBytes = stream.Read(buffer, 0, buffer.Length)) > 0 ||
timePosition <= duration)
{
while (waitinloop)
Thread.Sleep(500);
if (exitloop)
break;
Mp3Frame frame = null;
tempFileStream.Write(buffer, 0, readBytes);
tempFileStream.Flush();
//Read the stream starting from the point
//where we were at the last reading
using (MemoryStream ms = new MemoryStream(ReadStreamPartially(tempFileStream, streamPos, 1024 * 10)))
{
ms.Position = 0;
try
{
frame = Mp3Frame.LoadFromStream(ms);
}
catch { continue; } //Sometimes it throws Unexpected End of Stream exception
//Couldn't find the problem out, try catch is working for now
if (frame == null)
continue;
pos = ms.Position;
streamPos += pos;
}
if (!formatKnown)
{
format = new Mp3WaveFormat(frame.SampleRate, frame.ChannelMode == ChannelMode.Mono ? 1 : 2,
frame.FrameLength, frame.BitRate);
duration = (int)(Math.Ceiling(resp.ContentLength * 1d / format.AverageBytesPerSecond));
avgBytes = format.AverageBytesPerSecond;
formatKnown = true;
}
if (decompressor == null)
{
decompressor = new AcmMp3FrameDecompressor(format);
provider = new BufferedWaveProvider(decompressor.OutputFormat);
provider.BufferDuration = TimeSpan.FromSeconds(20);
waveOut.Init(provider);
waveOut.Play();
}
int decompressed = decompressor.DecompressFrame(frame, buffer, 0);
if (IsBufferNearlyFull(provider))
{
Thread.Sleep(500);
}
provider.AddSamples(buffer, 0, decompressed);
}
});
}
void disposeAllResources()
{
if (resp != null)
resp.Close();
if (stream != null)
stream.Close();
if (provider != null)
provider.ClearBuffer();
}
public void Pause()
{
if (waveOut.PlaybackState == PlaybackState.Playing && !waitinloop)
{
waitinloop = true;
waveOut.Pause();
Thread.Sleep(200);
}
}
public void Resume()
{
if (waveOut.PlaybackState == PlaybackState.Paused && waitinloop)
{
waitinloop = false;
waveOut.Play();
Thread.Sleep(200);
}
}
public void ForwardOrBackward(int targetTimePos)
{
waitinloop = false;
exitloop = true;
timeOffset = targetTimePos;
Thread.Sleep(100);
waveOut.Stop();
ticker.Stop();
this.Play();
}
public static byte[] ReadStreamPartially(System.IO.Stream stream, long offset, long count)
{
long originalPosition = 0;
if (stream.CanSeek)
{
originalPosition = stream.Position;
stream.Position = offset;
}
try
{
byte[] readBuffer = new byte[4096];
byte[] total = new byte[count];
int totalBytesRead = 0;
int byteRead;
while ((byteRead = stream.ReadByte()) != -1)
{
Buffer.SetByte(total, totalBytesRead, (byte)byteRead);
totalBytesRead++;
if (totalBytesRead == count)
{
stream.Position = originalPosition;
break;
}
}
if (totalBytesRead < count)
{
byte[] temp = new byte[totalBytesRead];
Buffer.BlockCopy(total, 0, temp, 0, totalBytesRead);
stream.Position = originalPosition;
return temp;
}
return total;
}
finally
{
if (stream.CanSeek)
{
stream.Position = originalPosition;
}
}
}
private bool IsBufferNearlyFull(BufferedWaveProvider bufferedWaveProvider)
{
return bufferedWaveProvider != null &&
bufferedWaveProvider.BufferLength - bufferedWaveProvider.BufferedBytes
< bufferedWaveProvider.WaveFormat.AverageBytesPerSecond / 4;
}
public int Duration
{
get
{
return duration;
}
}
public int TimePosition
{
get
{
return timePosition;
}
}
public int BufferedDuration
{
get { return (int)provider.BufferedDuration.TotalSeconds; }
}
public int TimeOffset
{
get
{
return timeOffset;
}
}
}
public enum State
{
Paused,
Playing,
Stopped,
Buffering
}
I can show you, how i would try to do it - assuming that the buffer of "waveOut" is not totally different to a DirectSound SecondaryBuffer.
Playing a Stream could behave like this:
There is data allready downloaded and maybe played and not downloaded data in between. To save this fractioned downloaded data, we need to add additional information to it - the time \ playorder.
To make it easier, we divide the File / Stream in atomic Subchunks of a fixed size, e.g. 100kByte. If the file is 5001 kByte -> 51 Subchunks are needed.
You can save them to a file in the downloaded order, and search for the id int you need - then reload the subchunk in your playbuffer. To do so you have to use this version of AddRange to load a subchunk:
public void AddRange( int from, int to )
https://msdn.microsoft.com/de-de/library/7fy67z6d(v=vs.110).aspx
I hope you get the point.
Load with other method and keep old stream
Let a playbuffer test if refilling his queque is necessary.
Only download a subchunk if it's not allready saved in memory or file.
A way reading to a file could be handled:
I am trying to retrieve an uploaded file from my webserver. As the client sends its files through a webform (random files), I need to parse the request to get the file out and to process it further on.
Basically, the code goes as:
HttpListenerContext context = listener.GetContext();
HttpListenerRequest request = context.Request;
StreamReader r = new StreamReader(request.InputStream, System.Text.Encoding.Default);
// this is the retrieved file from streamreader
string file = null;
while ((line = r.ReadLine()) != null){
// i read the stream till i retrieve the filename
// get the file data out and break the loop
}
// A byststream is created by converting the string,
Byte[] bytes = request.ContentEncoding.GetBytes(file);
MemoryStream mstream = new MemoryStream(bytes);
// do the rest
As a result, i am able to retrieve textfiles, but for all other files, they are corrupted.
Could someone tell me how to parse these HttplistnerRequests properly (or providing a lightweighted alternative)?
I think you are making things harder on yourself than necessary by doing this with an HttpListener rather than using the built in facilities of ASP.Net. But if you must do it this way here is some sample code. Note: 1) I'm assuming you're using enctype="multipart/form-data" on your <form>. 2) This code is designed to be used with a form containing only your <input type="file" /> if you want to post other fields or multiple files you'll have to change the code. 3) This is meant to be a proof of concept/example, it may have bugs, and is not particularly flexible.
static void Main(string[] args)
{
HttpListener listener = new HttpListener();
listener.Prefixes.Add("http://localhost:8080/ListenerTest/");
listener.Start();
HttpListenerContext context = listener.GetContext();
SaveFile(context.Request.ContentEncoding, GetBoundary(context.Request.ContentType), context.Request.InputStream);
context.Response.StatusCode = 200;
context.Response.ContentType = "text/html";
using (StreamWriter writer = new StreamWriter(context.Response.OutputStream, Encoding.UTF8))
writer.WriteLine("File Uploaded");
context.Response.Close();
listener.Stop();
}
private static String GetBoundary(String ctype)
{
return "--" + ctype.Split(';')[1].Split('=')[1];
}
private static void SaveFile(Encoding enc, String boundary, Stream input)
{
Byte[] boundaryBytes = enc.GetBytes(boundary);
Int32 boundaryLen = boundaryBytes.Length;
using (FileStream output = new FileStream("data", FileMode.Create, FileAccess.Write))
{
Byte[] buffer = new Byte[1024];
Int32 len = input.Read(buffer, 0, 1024);
Int32 startPos = -1;
// Find start boundary
while (true)
{
if (len == 0)
{
throw new Exception("Start Boundaray Not Found");
}
startPos = IndexOf(buffer, len, boundaryBytes);
if (startPos >= 0)
{
break;
}
else
{
Array.Copy(buffer, len - boundaryLen, buffer, 0, boundaryLen);
len = input.Read(buffer, boundaryLen, 1024 - boundaryLen);
}
}
// Skip four lines (Boundary, Content-Disposition, Content-Type, and a blank)
for (Int32 i = 0; i < 4; i++)
{
while (true)
{
if (len == 0)
{
throw new Exception("Preamble not Found.");
}
startPos = Array.IndexOf(buffer, enc.GetBytes("\n")[0], startPos);
if (startPos >= 0)
{
startPos++;
break;
}
else
{
len = input.Read(buffer, 0, 1024);
}
}
}
Array.Copy(buffer, startPos, buffer, 0, len - startPos);
len = len - startPos;
while (true)
{
Int32 endPos = IndexOf(buffer, len, boundaryBytes);
if (endPos >= 0)
{
if (endPos > 0) output.Write(buffer, 0, endPos-2);
break;
}
else if (len <= boundaryLen)
{
throw new Exception("End Boundaray Not Found");
}
else
{
output.Write(buffer, 0, len - boundaryLen);
Array.Copy(buffer, len - boundaryLen, buffer, 0, boundaryLen);
len = input.Read(buffer, boundaryLen, 1024 - boundaryLen) + boundaryLen;
}
}
}
}
private static Int32 IndexOf(Byte[] buffer, Int32 len, Byte[] boundaryBytes)
{
for (Int32 i = 0; i <= len - boundaryBytes.Length; i++)
{
Boolean match = true;
for (Int32 j = 0; j < boundaryBytes.Length && match; j++)
{
match = buffer[i + j] == boundaryBytes[j];
}
if (match)
{
return i;
}
}
return -1;
}
To help you better understand what the code above is doing, here is what the body of the HTTP POST looks like:
Content-Type: multipart/form-data; boundary=----WebKitFormBoundary9lcB0OZVXSqZLbmv
------WebKitFormBoundary9lcB0OZVXSqZLbmv
Content-Disposition: form-data; name="my_file"; filename="Test.txt"
Content-Type: text/plain
Test
------WebKitFormBoundary9lcB0OZVXSqZLbmv--
I've left out the irrelevant headers. As you can see, you need to parse the body by scanning through to find the beginning and ending boundary sequences, and drop the sub headers that come before the content of your file. Unfortunately you cannot use StreamReader because of the potential for binary data. Also unfortunate is the fact that there is no per file Content-Length (the Content-Length header for the request specifies the total length of the body including boundaries, sub-headers, and spacing.
You can't use StreamReader because it is meant to read streams in which the bytes are in the UTF8. Instead, you want to read the contents of the stream to a receive buffer, remove all the stuff you don't need, get the file extension of the uploaded file, extract the contents of the uploaded file, then save the file contents to a new file. The code I show in this post assumes your form looks like this:
<form enctype="multipart/form-data" method="POST" action="/uploader">
<input type="file" name="file">
<input type="submit">
</form>
As you can see, the code is only meant to handle a form that only has the file. Since there is no way to extract the contents of a file on the server from a application/x-www-form-urlencoded form, so you have to include the "multipart/form-data".
First, for this method of handling uploaded files, you will first need this little bit of code:
using System;
using System.IO;
using System.Text;
using System.Net;
using System.Collections.Generic;
Second, you need to read the contents of the request.InputStream to a receive buffer, or a byte[]. We do this by making a byte[] buffer with the length of the Content-Length header sent by the browser. Then, we read the contents of the request.InputStream to the buffer. The code would look like this:
int len = int.Parse(request.Headers["Content-Length"]);
byte[] buffer = new byte[len];
request.InputStream.Read(buffer, 0, len);
The stream will look somewhat like this:
------WebKitFormBoundary9lcB0OZVXSqZLbmv
Content-Disposition: form-data; name="file"; filename="example-file.txt"
Content-Type: text/plain
file contents here
------WebKitFormBoundary9lcB0OZVXSqZLbmv--
Next, you need to get the file extension of the uploaded file. We can do this using this code:
string fileExtension = Encoding.UTF8.GetString(bytes).Split("\r\n")[1].Split("filename=\"")[1].Replace("\"", "").Split('.')[^1];
Then, we need to get the contents of the file. We do this by removing the stuff at the beginning (the -----WebKitFormBoundary, the Content-Disposition, the Content-Type, and a blank line), then removing the last line of the request body, plus an extra \r\n at the end. Here is the code that does just that:
// note that the variable buffer is the byte[], and the variable bytes is the List<byte>
string stringBuffer = Encoding.UTF8.GetString(buffer);
List<byte> bytes = new List<byte>(buffer);
string[] splitString = stringBuffer.Split('\n');
int lengthOfFourLines = splitString[0].Length + splitString[1].Length +
splitString[2].Length + splitString[3].Length + 4;
bytes.RemoveRange(0, lengthOfFourLines);
int lengthOfLastLine = splitString[^2].Length+2;
bytes.RemoveRange(bytes.Count - lengthOfLastLine, lengthOfLastLine);
buffer = bytes.ToArray();
Finally, we need to save the contents to a file. The code below generates a random file name with the user-specified file extension, and saves the files contents to it.
string fname = "";
string[] chars = "q w e r t y u i o p a s d f g h j k l z x c v b n m Q W E R T Y U I O P A S D F G H J K L Z X C V B N M 1 2 3 4 5 6 7 8 9 0".Split(" ");
for (int i = 0; i < 10; i++)
{
fname += chars[new Random().Next(chars.Length)];
}
fname += fileExtension;
FileStream file = File.Create(fname);
file.Write(buffer);
file.Close();
Here is the whole code put together:
public static void Main()
{
var listener = new HttpListener();
listener.Prefixes.Add("http://localhost:8080/");
listener.Start();
while(true)
{
HttpListenerContext context = listener.GetContext();
HttpListenerRequest request = context.Request;
HttpListenerResponse response = context.Response;
if(request.HttpMethod=="POST") SaveFile(request);
response.OutputStream.Write(Encoding.UTF8.GetBytes("file successfully uploaded"));
response.OutputStream.Close();
}
}
void SaveFile(HttpListenerRequest request)
{
int len = (int)request.ContentLength64;
Console.WriteLine(len);
byte[] buffer = new byte[len];
request.InputStream.Read(buffer, 0, len);
string stringBuffer = Encoding.UTF8.GetString(buffer);
Console.WriteLine(stringBuffer.Replace("\r\n","\\r\\n\n"));
string fileExtension = stringBuffer.Split("\r\n")[1]
.Split("filename=\"")[1]
.Replace("\"", "")
.Split('.')[^1]
;
List<byte> bytes = new List<byte>(buffer);
string[] splitString = stringBuffer.Split('\n');
int lengthOfFourLines = splitString[0].Length + splitString[1].Length + splitString[2].Length + splitString[3].Length + 4;
bytes.RemoveRange(0, lengthOfFourLines);
int lengthOfLastLine = splitString[^2].Length+2;
bytes.RemoveRange(bytes.Count - lengthOfLastLine, lengthOfLastLine);
buffer = bytes.ToArray();
string fname = "";
string[] chars = "q w e r t y u i o p a s d f g h j k l z x c v b n m Q W E R T Y U I O P A S D F G H J K L Z X C V B N M 1 2 3 4 5 6 7 8 9 0".Split(" ");
for (int i = 0; i < 10; i++)
{
fname += chars[new Random().Next(chars.Length)];
}
fname += "." + fileExtension;
FileStream file = File.Create(fname);
file.Write(buffer);
file.Close();
}
Also, if you want to send an uploaded file to the client, here is a useful function that sends the file to the client.
// Make sure you are using System.IO, and System.Net when making this function.
// Also make sure you set the content type of the response before calling this function.
// fileName is the name of the file you want to send to the client, and output is the response.OutputStream.
public static void SendFile(string fileName, Stream output)
{
FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
fs.CopyTo(output);
fs.Close();
output.Close();
}
The problem is you are reading the file as text.
You need to read the file as a bytearray instead and using the BinaryReader is better and easier to use than StreamReader:
Byte[] bytes;
using (System.IO.BinaryReader r = new System.IO.BinaryReader(request.InputStream))
{
// Read the data from the stream into the byte array
bytes = r.ReadBytes(Convert.ToInt32(request.InputStream.Length));
}
MemoryStream mstream = new MemoryStream(bytes);
May have bugs, test thoroughly. This one gets all post, get, and files.
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.Net;
using System.Text;
using System.Web;
namespace DUSTLauncher
{
class HttpNameValueCollection
{
public class File
{
private string _fileName;
public string FileName { get { return _fileName ?? (_fileName = ""); } set { _fileName = value; } }
private string _fileData;
public string FileData { get { return _fileData ?? (_fileName = ""); } set { _fileData = value; } }
private string _contentType;
public string ContentType { get { return _contentType ?? (_contentType = ""); } set { _contentType = value; } }
}
private NameValueCollection _get;
private Dictionary<string, File> _files;
private readonly HttpListenerContext _ctx;
public NameValueCollection Get { get { return _get ?? (_get = new NameValueCollection()); } set { _get = value; } }
public NameValueCollection Post { get { return _ctx.Request.QueryString; } }
public Dictionary<string, File> Files { get { return _files ?? (_files = new Dictionary<string, File>()); } set { _files = value; } }
private void PopulatePostMultiPart(string post_string)
{
var boundary_index = _ctx.Request.ContentType.IndexOf("boundary=") + 9;
var boundary = _ctx.Request.ContentType.Substring(boundary_index, _ctx.Request.ContentType.Length - boundary_index);
var upper_bound = post_string.Length - 4;
if (post_string.Substring(2, boundary.Length) != boundary)
throw (new InvalidDataException());
var raw_post_strings = new List<string>();
var current_string = new StringBuilder();
for (var x = 4 + boundary.Length; x < upper_bound; ++x)
{
if (post_string.Substring(x, boundary.Length) == boundary)
{
x += boundary.Length + 1;
raw_post_strings.Add(current_string.ToString().Remove(current_string.Length - 3, 3));
current_string.Clear();
continue;
}
current_string.Append(post_string[x]);
var post_variable_string = current_string.ToString();
var end_of_header = post_variable_string.IndexOf("\r\n\r\n");
if (end_of_header == -1) throw (new InvalidDataException());
var filename_index = post_variable_string.IndexOf("filename=\"", 0, end_of_header);
var filename_starts = filename_index + 10;
var content_type_starts = post_variable_string.IndexOf("Content-Type: ", 0, end_of_header) + 14;
var name_starts = post_variable_string.IndexOf("name=\"") + 6;
var data_starts = end_of_header + 4;
if (filename_index == -1) continue;
var filename = post_variable_string.Substring(filename_starts, post_variable_string.IndexOf("\"", filename_starts) - filename_starts);
var content_type = post_variable_string.Substring(content_type_starts, post_variable_string.IndexOf("\r\n", content_type_starts) - content_type_starts);
var file_data = post_variable_string.Substring(data_starts, post_variable_string.Length - data_starts);
var name = post_variable_string.Substring(name_starts, post_variable_string.IndexOf("\"", name_starts) - name_starts);
Files.Add(name, new File() { FileName = filename, ContentType = content_type, FileData = file_data });
continue;
}
}
private void PopulatePost()
{
if (_ctx.Request.HttpMethod != "POST" || _ctx.Request.ContentType == null) return;
var post_string = new StreamReader(_ctx.Request.InputStream, _ctx.Request.ContentEncoding).ReadToEnd();
if (_ctx.Request.ContentType.StartsWith("multipart/form-data"))
PopulatePostMultiPart(post_string);
else
Get = HttpUtility.ParseQueryString(post_string);
}
public HttpNameValueCollection(ref HttpListenerContext ctx)
{
_ctx = ctx;
PopulatePost();
}
}
}
I like #paul-wheeler answer. However I needed to modify their code to include some additional data (In this case, the directory structure).
I'm using this code to upload files:
var myDropzone = $("#fileDropZone");
myDropzone.dropzone(
{
url: "http://" + self.location.hostname + "/Path/Files.html,
method: "post",
createImageThumbnails: true,
previewTemplate: document.querySelector('#previewTemplateId').innerHTML,
clickable: false,
init: function () {
this.on('sending', function(file, xhr, formData){
// xhr is XMLHttpRequest
var name = file.fullPath;
if (typeof (file.fullPath) === "undefined") {
name = file.name;
}
formData.append('fileNameWithPath', name);
});
}
});
Here is #paul-wheeler modified code. Thanks #paul-wheeler.
public class FileManager
{
public static void SaveFile(HttpListenerRequest request, string savePath)
{
var tempFileName = Path.Combine(savePath, $"{DateTime.Now.Ticks}.tmp");
if (!Directory.Exists(savePath))
{
Directory.CreateDirectory(savePath);
}
var (res, fileName) = SaveTmpFile(request, tempFileName);
if (res)
{
var filePath = Path.Combine(savePath, fileName);
var fileDir = filePath.Substring(0, filePath.LastIndexOf(Path.DirectorySeparatorChar));
if (!Directory.Exists(fileDir))
{
Directory.CreateDirectory(fileDir);
}
if (File.Exists(filePath))
{
File.Delete(filePath);
}
File.Move(tempFileName, filePath);
}
}
private static (bool, string) SaveTmpFile(HttpListenerRequest request, string tempFileName)
{
var enc = request.ContentEncoding;
var boundary = GetBoundary(request.ContentType);
var input = request.InputStream;
byte[] boundaryBytes = enc.GetBytes(boundary);
var boundaryLen = boundaryBytes.Length;
using (FileStream output = new FileStream(tempFileName, FileMode.Create, FileAccess.Write))
{
var buffer = new byte[1024];
var len = input.Read(buffer, 0, 1024);
var startPos = -1;
// Get file name and relative path
var strBuffer = Encoding.Default.GetString(buffer);
var strStart = strBuffer.IndexOf("fileNameWithPath") + 21;
if (strStart < 21)
{
Logger.LogError("File name not found");
return (false, null);
}
var strEnd = strBuffer.IndexOf(boundary, strStart) - 2;
var fileName = strBuffer.Substring(strStart, strEnd - strStart);
fileName = fileName.Replace('/', Path.DirectorySeparatorChar);
// Find start boundary
while (true)
{
if (len == 0)
{
Logger.LogError("Find start boundary not found");
return (false, null);
}
startPos = IndexOf(buffer, len, boundaryBytes);
if (startPos >= 0)
{
break;
}
else
{
Array.Copy(buffer, len - boundaryLen, buffer, 0, boundaryLen);
len = input.Read(buffer, boundaryLen, 1024 - boundaryLen);
}
}
// Advance to data
var foundData = false;
while (!foundData)
{
while (true)
{
if (len == 0)
{
Logger.LogError("Preamble not Found");
return (false, null);
}
startPos = Array.IndexOf(buffer, enc.GetBytes("\n")[0], startPos);
if (startPos >= 0)
{
startPos++;
break;
}
else
{
// In case read in line is longer than buffer
len = input.Read(buffer, 0, 1024);
}
}
var currStr = Encoding.Default.GetString(buffer).Substring(startPos);
if (currStr.StartsWith("Content-Type:"))
{
// Go past the last carriage-return\line-break. (\r\n)
startPos = Array.IndexOf(buffer, enc.GetBytes("\n")[0], startPos) + 3;
break;
}
}
Array.Copy(buffer, startPos, buffer, 0, len - startPos);
len = len - startPos;
while (true)
{
var endPos = IndexOf(buffer, len, boundaryBytes);
if (endPos >= 0)
{
if (endPos > 0) output.Write(buffer, 0, endPos - 2);
break;
}
else if (len <= boundaryLen)
{
Logger.LogError("End Boundaray Not Found");
return (false, null);
}
else
{
output.Write(buffer, 0, len - boundaryLen);
Array.Copy(buffer, len - boundaryLen, buffer, 0, boundaryLen);
len = input.Read(buffer, boundaryLen, 1024 - boundaryLen) + boundaryLen;
}
}
return (true, fileName);
}
}
private static int IndexOf(byte[] buffer, int len, byte[] boundaryBytes)
{
for (int i = 0; i <= len - boundaryBytes.Length; i++)
{
var match = true;
for (var j = 0; j < boundaryBytes.Length && match; j++)
{
match = buffer[i + j] == boundaryBytes[j];
}
if (match)
{
return i;
}
}
return -1;
}
private static string GetBoundary(string ctype)
{
return "--" + ctype.Split(';')[1].Split('=')[1];
}
}
using Microsoft.AspNetCore.WebUtilities;
using Microsoft.Net.Http.Headers;
var contentType = MediaTypeHeaderValue.Parse(context.Request.ContentType);
var boundary = HeaderUtilities.RemoveQuotes(contentType.Boundary).Value;
var multipartReader = new MultipartReader(boundary, context.Request.InputStream);
var section = (await multipartReader.ReadNextSectionAsync()).AsFileSection();
var fileName = section.FileName;
var fileStream = section.FileStream;
for a given HttpListenerRequest req and a string path the following code saves a file (worked for text file but also png file)
int len = (int)req.ContentLength64;
byte[] buffer = new byte[len];
int totalRead = 0;
while(totalRead < len){
// InputStream.Read does not read always read full stream (so loop until it has)
totalRead += req.InputStream.Read(buffer, totalRead, len - totalRead);
}
string stringBuffer = Encoding.UTF8.GetString(buffer);
string startTag = stringBuffer.Substring(0, stringBuffer.IndexOf("\r\n\r\n") + 4);
string endTag = stringBuffer.Substring(stringBuffer.IndexOf("\r\n------WebKitFormBoundary"));
List<byte> bytes = new List<byte>(buffer);
bytes = bytes.GetRange(startTag.Length, len - (startTag.Length + endTag.Length));
buffer = bytes.ToArray();
File.WriteAllBytes(path, buffer);
(build on top of copee moo solution)