How can I append the content of a file (any file extension) to an existing file with the same extension?
I have tried this
System.IO.File.AppendAllLines(dest_path, System.IO.File.ReadAllLines(fi));
but this works only for the .txt files
I understand that you want to concatenate a set of files together, like the DOS command copy /b a.pdf + b.pdf both.pdf - Reading all the bytes of N number of files and appending them all to a single file.
using (var stream = new FileStream(pathOfFileToAppendTo, FileMode.Append))
{
foreach(var pathOfFileToAppend in ...) {
var bytes = File.ReadAllBytes(pathOfFileToAppend);
stream.Write(bytes, 0, bytes.Length);
}
}
If the files you want to append are very large, you might need a streaming approach instead of reading them all into memory with ReadAllBytes. The ... is some array/list/enumerable of string filenames like you might get from Directory.GetFiles but it can be any set of filepaths.
Related
I have a number of a zipped files in a folder stored on a Samsung EVO 970 SSD. Each zip file is 2GB+(while compressed) with 200K+ text files contained within, each file being between 5 to 1.5MB, essentially a large number of small text files.
Rather than extract the zip file and process each text file individually to an SSD, I'm trying to load each zip file in memory in full at the start of the processing and then read each file like shown at the end here.
My (maybe naive ) thinking is that if I could figure out a way to hold the whole zip file contents in the ram and process the text contents without decompressing the zip contents to disk, I would see material boost in the processing performance.
Currently it is taking about 10millisec on average to process every single text file even with the approach taken below.
var myMS = new MemoryStream();
using(var file = File.OpenRead(zipFile))
{
file.CopyTo(myMS);
using(var zip = new ZipArchive(myMS, ZipArchiveMode.Read))
{
foreach(var entry in zip.Entries)
{
using(var reader = new StreamReader(entry.Open(),Encoding.UTF8))
{
string fileContents = reader.ReadToEnd();
//do something with the file
My question is does this approach make sense ? Given that the total number of files, including all zip files is in the millions, I could be sat here for a week waiting for processing to finish.
I would like to know if it is possible to check the size of the zip file that is being created dynamically, because I am reading a directory and generate a 19 MB zip and I would like two zips instead to be created, one 10MB and the other 9MB. However, when I give a .Length in the zip file inside my loop it says the size is 0. When I finish adding the files it says that is 19MB. Would anyone know how to do this?
I am using only System.IO.Compression to this task.
here is some example to show how I am trying
String FilePath = "D:\Invoices";
string[] oFiles = Directory.GetFiles(FilePath,"*.pdf");
string name = DateTime.Now.Ticks.ToString()+".zip";
using(FileStream archive1 = File.Open(name,FileMode.Create))
{
using(var arch = new ZipArchive(archive1,ZipArchiveMode.Update))
{
for(int i =0; i<oFiles.Length;i++)
{
var fileinf = new FileInfo(oFiles[i]);
arch.CreateEntryFromFile(fileinf.FullName,fileinf.Name);
//here the zip file is always 0
Console.WriteLine(archive1.Length);
}
}
}
//here the zip file is updated
From the documentation:
When you set the mode to Update … The content of the entire archive is held in memory, and no data is written to the underlying file or stream until the archive is disposed.
If you want to be able to read the size of the file as you're adding things, you need to use ZipArchiveMode.Create.
Otherwise, you should use the ZipArchiveEntry.CompressedSize property to monitor how much you've added to the archive.
I am trying to create a function that will retrieve all the uploaded files (which are now saved as byte in the database) and download it in a single zip file. I currently have 6000 files to download (and the number could grow).
The functionality is already working (from retrieval to download) if I limit the number of files being downloaded, otherwise, I get an OutOfMemoryException on the ForEach loop.
Here's a pseudo code: (files variable is a list of byte array and file name)
var files = getAllFilesFromDB();
foreach (var file in files)
{
var tempFilePath = Path.Combine(path, filename);
using (FileStream stream = new FileStream(tempfileName, FileMode.Create, FileAccess.ReadWrite))
{
stream.Write(file.byteArray, 0, file.byteArray.Length);
}
}
private readonly IEntityRepository<File> fileRepository;
IEnumerable<FileModel> getAllFilesFromDb()
{
return fileRepository.Select(f => new FileModel(){ fileData = f.byteArray, filename = f.fileName});
}
My question is, is there any other way to do this to avoid getting such errors?
To avoid this problem, you could avoid loading all the contents of all the files in one go. Most likely you will need to split your database call in to two database calls.
Retrieve a list of all the files without their contents but with some identifier - like the PK of the table.
A method which retrieves the contents of an individual file.
Then your (pseudo)code becomes
get list of all files
for each file
get the file contents
write the file to disk
Another possibility is to alter the way your query works currently, so that it uses deferred execution - this means it will not actually load all the files at once, but stream them one at a time from the database - but without seeing more code from your repository implementation, I cannot/ will not guess the right solution for you.
Iam trying to merge two .wav files into another file. but I could see only first file's data in the created file.
but the newly created file occupies the space which is equals the sum of the size of the source files.
foreach (string sourceFile in fileNamesList)
{
FileStream file= File.Open(sourceFile, FileMode.Open);
FileStream outFile = File.Open(output, FileMode.Append,FileAccess.Write);
byte[] buffer = new byte[file.Length];
int read;
if ((read=file.Read(buffer, 0, (int)file.Length))>0)
{
outFile.Write(buffer, 0, read);
}
file.Close();
file.Dispose();
outFile.Close();
outFile.Dispose();
}
thanks
You can't just concatenate two WAV files because they have a header which defines the format, number of channels, sample rate, length etc.
You will need to read and parse the header file for each separate WAV file and then write a new header to a new file with the correct data and then append the data contents from each WAV file.
You will not easily be able to concatenate two WAV files which have different sample rates or number of channels, but otherwise it's not too hard (once you've worked out the header format).
See here for details about the header format:
https://ccrma.stanford.edu/courses/422/projects/WaveFormat/
http://en.wikipedia.org/wiki/WAV
Perhaps the easiest way will to be to use a third party tool such as Naudio to do this, as described here:
How to join 2 or more .WAV files together programatically?
How can I read content of a text file inside a zip archive?
For example I have an archive qwe.zip, and insite it there's a file asd.txt, so how can I read contents of that file?
Is it possible to do without extracting the whole archive? Because it need to be done quick, when user clicks a item in a list, to show description of the archive (it needed for plugin system for another program). So extracting a whole archive isn't the best solution... because it might be few Mb, which will take at least few seconds or even more to extract... while only that single file need to be read.
You could use a library such as SharpZipLib or DotNetZip to unzip the file and fetch the contents of individual files contained inside. This operation could be performed in-memory and you don't need to store the files into a temporary folder.
Unzip to a temp-folder take the file and delete the temp-data
public static void Decompress(string outputDirectory, string zipFile)
{
try
{
if (!File.Exists(zipFile))
throw new FileNotFoundException("Zip file not found.", zipFile);
Package zipPackage = ZipPackage.Open(zipFile, FileMode.Open, FileAccess.Read);
foreach (PackagePart part in zipPackage.GetParts())
{
string targetFile = outputDirectory + "\\" + part.Uri.ToString().TrimStart('/');
using (Stream streamSource = part.GetStream(FileMode.Open, FileAccess.Read))
{
using (Stream streamDestination = File.OpenWrite(targetFile))
{
Byte[] arrBuffer = new byte[10000];
int iRead = streamSource.Read(arrBuffer, 0, arrBuffer.Length);
while (iRead > 0)
{
streamDestination.Write(arrBuffer, 0, iRead);
iRead = streamSource.Read(arrBuffer, 0, arrBuffer.Length);
}
}
}
}
}
catch (Exception)
{
throw;
}
}
Although late in the game and the question is already answered, in hope that this still might be useful for others who find this thread, I would like to add another solution.
Just today I encountered a similar problem when I wanted to check the contents of a ZIP file with C#. Other than NewProger I cannot use a third party library and need to stay within the out-of-the-box .NET classes.
You can use the System.IO.Packaging namespace and use the ZipPackage class. If it is not already included in the assembly, you need to add a reference to WindowsBase.dll.
It seems, however, that this class does not always work with every Zip file. Calling GetParts() may return an empty list although in the QuickWatch window you can find a property called _zipArchive that contains the correct contents.
If this is the case for you, you can use Reflection to get the contents of it.
On geissingert.com you can find a blog article ("Getting a list of files from a ZipPackage") that gives a coding example for this.
SharpZipLib or DotNetZip may still need to get/read the whole .zip file to unzip a file. Actually, there is still method could make you just extract special file from the .zip file without reading the entire .zip file but just reading small segment.
I needed to have insights into Excel files, I did it like so:
using (var zip = ZipFile.Open("ExcelWorkbookWithMacros.xlsm", ZipArchiveMode.Update))
{
var entry = zip.GetEntry("xl/_rels/workbook.xml.rels");
if (entry != null)
{
var tempFile = Path.GetTempFileName();
entry.ExtractToFile(tempFile, true);
var content = File.ReadAllText(tempFile);
[...]
}
}