From SharePoint, I get a "Stream" for a file. I want to copy this entire file from the internet to a local file on the PC, but I want to have status while this download is occurring. How? FileStream and StreamReader seem to have bytes vs char differences when not doing a full "CopyTo" which doesn't have progress updates. There has to be a cleaner way...
using (var sr = new StreamReader(fileData.Value))
{
using (FileStream fs = new FileStream(localFile + "_tmp", FileMode.Create))
{
byte[] block = new byte[1024];
// only guessing something like this is necessary...
int count = (int)Math.Min(sr.BaseStream.Length - sr.BaseStream.Position, block.Length);
while (sr.BaseStream.Position < sr.BaseStream.Length)
{
// read requires char[]
sr.Read(block, 0, count);
// write requires byte[]
fs.Write(block, 0, count);
Log("Percent complete: " + (sr.BaseStream.Position / sr.BaseStream.Length));
count = (int)Math.Min(sr.BaseStream.Length - sr.BaseStream.Position, block.Length);
}
}
}
Just had to use BinaryReader instead of StreamReader. Easy Peasy.
Related
I'm working with GZipStream at the moment using .net 3.5.
I have two methods listed below. As input file I use text file which consists of chars 's'. Size of the file is 2MB. This code works fine if I use .net 4.5 but with .net 3.5 after compress and decompress I get file of size 435KB which of course isn't the same with source file.
If I try to decompress file via WinRAR it is also looks good (the same with source file).
If I try decompress file using GZipStream from .net4.5 (file compressed via GZipStream from .net 3.5) the result is bad.
UPD:
In general I really need to read the file as several separate gzip chunks, in this case all the bytes of copressed files are read at one call of the Read() method so I still don't understand why decompressing doesn't works.
public void CompressFile()
{
string fileIn = #"D:\sin2.txt";
string fileOut = #"D:\sin2.txt.pgz";
using (var fout = File.Create(fileOut))
{
using (var fin = File.OpenRead(fileIn))
{
using (var zip = new GZipStream(fout, CompressionMode.Compress))
{
var buffer = new byte[1024 * 1024 * 10];
int n = fin.Read(buffer, 0, buffer.Length);
zip.Write(buffer, 0, n);
}
}
}
}
public void DecompressFile()
{
string fileIn = #"D:\sin2.txt.pgz";
string fileOut = #"D:\sin2.1.txt";
using (var fsout = File.Create(fileOut))
{
using (var fsIn = File.OpenRead(fileIn))
{
var buffer = new byte[1024 * 1024 * 10];
int n;
while ((n = fsIn.Read(buffer, 0, buffer.Length)) > 0)
{
using (var ms = new MemoryStream(buffer, 0, n))
{
using (var zip = new GZipStream(ms, CompressionMode.Decompress))
{
int nRead = zip.Read(buffer, 0, buffer.Length);
fsout.Write(buffer, 0, nRead);
}
}
}
}
}
}
You're trying to decompress each "chunk" as if it's a separate gzip file. Don't do that - just read from the GZipStream in a loop:
using (var fsout = File.Create(fileOut))
{
using (var fsIn = File.OpenRead(fileIn))
{
using (var zip = new GZipStream(fsIn, CompressionMode.Decompress))
{
var buffer = new byte[1024 * 32];
int bytesRead;
while ((bytesRead = zip.Read(buffer, 0, buffer.Length)) > 0)
{
fsout.Write(buffer, 0, bytesRead);
}
}
}
}
Note that your compression code should look similar, reading in a loop rather than assuming a single call to Read will read all the data.
(Personally I'd skip fsIn, and just use new GZipStream(File.OpenRead(fileIn)) but that's just a personal preference.)
First, as #Jon Skeet mentioned, you are not using Stream.Read method correctly. It doesn't matter if your buffer is big enough or not, the stream is allowed to return less bytes than requested, with zero indicating no more, so reading from stream should always be performed in a loop.
However the main problem in your decompress code is the way you share the buffer. Your read the input into a buffer, than wrap it in a MemoryStream (note that the constructor used does not make a copy of the passed array, but actually sets it as it's internal buffer), and then you try to read and write to that buffer at the same time. Taking into account that decompressing writes data "faster" than reading, it's surprising that your code works at all.
The correct implementation is quite simple
static void CompressFile()
{
string fileIn = #"D:\sin2.txt";
string fileOut = #"D:\sin2.txt.pgz";
using (var input = File.OpenRead(fileIn))
using (var output = new GZipStream(File.Create(fileOut), CompressionMode.Compress))
Write(input, output);
}
static void DecompressFile()
{
string fileIn = #"D:\sin2.txt.pgz";
string fileOut = #"D:\sin2.1.txt";
using (var input = new GZipStream(File.OpenRead(fileIn), CompressionMode.Decompress))
using (var output = File.Create(fileOut))
Write(input, output);
}
static void Write(Stream input, Stream output, int bufferSize = 10 * 1024 * 1024)
{
var buffer = new byte[bufferSize];
for (int readCount; (readCount = input.Read(buffer, 0, buffer.Length)) > 0;)
output.Write(buffer, 0, readCount);
}
I have a path which has a list of files.
foreach (var file in Directory.GetFiles(networkpath))
{
Stream s=file.
}
I want to convert the file into Stream.How to proceed further?
Is this what you need?
foreach (var file in Directory.GetFiles(networkpath))
{
using (FileStream fs = File.Open(file, FileMode.Open))
{
}
}
You can safely read file using FileStream in C#. To be sure the whole file is correctly read, you should call FileStream.Read method in a loop, even if in the most cases the whole file is read in a single call of FileStream.Read method.
First create FileStream to open a file for reading. Then call FileStream.Read in a loop until the whole file is read. Finally close the stream.
using System.IO;
public static byte[] ReadFile(string filePath)
{
byte[] buffer;
FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
try
{
int length = (int)fileStream.Length; // get file length
buffer = new byte[length]; // create buffer
int count; // actual number of bytes read
int sum = 0; // total number of bytes read
// read until Read method returns 0 (end of the stream has been reached)
while ((count = fileStream.Read(buffer, sum, length - sum)) > 0)
sum += count; // sum is a buffer offset for next reading
}
finally
{
fileStream.Close();
}
return buffer;
}
Change your file path to suit your code!Add this inside your loop!
FileStream fStream = new FileStream(#"c:\file.txt", FileMode.Open);
try
{
// read from file or write to file
}
finally
{
fStream.Close();
}
My company run an application that have to archive many kinds of files into some distants servers. The application works well but can't handle files larger than 1GB.
Here is the current function use to load the files to be uploaded to the distant server :
FileStream fs = File.OpenRead(fileToUploadPath);
byte[] fileArray = new byte[fs.Length];
fs.Read(fileArray, 0, fs.Length);
The byte array (when loaded successfully) was then splited into 100Mb bytes arrays and sent to the local server (using some WSDL web services) with the following function :
localServerWebService.SendData(subFileArray, filename);
I changed the function responsible for the file reading to use BufferendStream and I also wanted to improve the Webservice part so that it doesn't have to create a new stream at each call. I thought of somethings like this :
FileInfo source = new FileInfo(fileName);
using (FileStream reader = File.OpenRead(fileName))
{
using (FileStream distantWriter = localServerWebService.CreateWriteFileStream(fileName))
{
using (BufferedStream buffReader = new BufferedStream(reader))
{
using (BufferedStream buffWriter = new BufferedStream(distantWriter))
{
byte[] buffer = new byte[BUFFER_SIZE];
int bytesRead = 0;
long bytesToRead = source.Length;
while (bytesToRead > 0)
{
int nbBytesRead = buffReader.Read(buffer, 0, buffer.Length);
buffWriter.Write(buffer, 0, nbBytesRead);
bytesRead += nbBytesRead;
bytesToRead -= nbBytesRead;
}
}
}
}
}
But this code can't compile and always give me the error Cannot convert MyNameSpace.FileStream into System.IO.FileStream at line using (FileStream distantWriter = localServerWebService.CreateWriteFileStream(fileName)). I can't cast MyNameSpace.FileStream into System.IO.FileStream either.
The web service method :
[WebMethod]
public FileStream CreateWriteFileStream(String fileName)
{
String RepVaultUP =
System.Configuration.ConfigurationSettings.AppSettings.Get("SAS_Upload");
String desFile = Path.Combine(RepVaultUP, fileName);
return File.Open(desFile, FileMode.Create, FileAccess.Write);
}
So can you guys please explain to me why is this not working?
P.S.: English is not my mothertong so I hope what i wrote is clearly undestandable.
using (Stream fileStream = System.IO.File.OpenWrite("D:\sample.svg"))
{
byte[] buffer = new byte[8 * 1024];
int len;
while ((len = SvgStream.Read(buffer, 0, buffer.Length)) > 0)
{
fileStream.Write(buffer, 0, len);
}
}
I have this code for converting a PPT to SVG. SvgStream contains the PPT Slides. I don't want to store the converted SVG file on a physical path like D:\sample.svg. Is it possible to store it on an object that is not a physical path?
Is it possible to store it on an object that is not a physical path?
Sure. Create a MemoryStream instead of a FileStream if you want to stream into memory rather than the file system.
And while I'm here: you might want to use the CopyTo method rather than this tedious business of buffering it over one page at a time.
I saved it to a string:
SvgStream = new MemoryStream();
sld.WriteAsSvg(SvgStream);
SvgStream.Position = 0;
string[] svgArray = new string[MAX];
//instead of using(var fileStream = File.IO.......
//I came up with this:
var sr = new StreamReader(SvgStream);
svgArray[i] = sr.ReadToEnd();
I have some code that downloads gzipped files, and decompresses them. The problem is, I can't get it to decompress the whole file, it only reads the first 4096 bytes and then about 500 more.
Byte[] buffer = new Byte[4096];
int count = 0;
FileStream fileInput = new FileStream("input.gzip", FileMode.Open, FileAccess.Read, FileShare.Read);
FileStream fileOutput = new FileStream("output.dat", FileMode.Create, FileAccess.Write, FileShare.None);
GZipStream gzipStream = new GZipStream(fileInput, CompressionMode.Decompress, true);
// Read from gzip steam
while ((count = gzipStream.Read(buffer, 0, buffer.Length)) > 0)
{
// Write to output file
fileOutput.Write(buffer, 0, count);
}
// Close the streams
...
I've checked the downloaded file; it's 13MB when compressed, and contains one XML file. I've manually decompressed the XML file, and the content is all there. But when I do it with this code, it only outputs the very beginning of the XML file.
Anyone have any ideas why this might be happening?
EDIT
Try not leaving the GZipStream open:
GZipStream gzipStream = new GZipStream(fileInput, CompressionMode.Decompress,
false);
or
GZipStream gzipStream = new GZipStream(fileInput, CompressionMode.Decompress);
I ended up using a gzip executable to do the decompression instead of a GZipStream. It can't handle the file for some reason, but the executable can.
Same thing happened to me. In my case only reads up to 6 lines and then reached end of file. So I realized that although the extension is gz, it was compressed by another algorithm not supported by GZipStream. So I used SevenZipSharp library and it worked. This is my code
You can use SevenZipSharp library
using (var input = File.OpenRead(lstFiles[0]))
{
using (var ds = new SevenZipExtractor(input))
{
//ds.ExtractionFinished += DsOnExtractionFinished;
var mem = new MemoryStream();
ds.ExtractFile(0, mem);
using (var sr = new StreamReader(mem))
{
var iCount = 0;
String line;
mem.Position = 0;
while ((line = sr.ReadLine()) != null && iCount < 100)
{
iCount++;
LstOutput.Items.Add(line);
}
}
}
}
Are you calling Close or Flush on fileOutput? (Or just wrap it in a using, which is recommended practice.) If you don't the file might not be flushed to disk when your program ends.