Develop Reference

How to convert binary text to byte array

I have got a text file which name is "file.txt".
There is binary text like "11100100100" in that file and I am trying to read the file and convert the binary into a bytearray.
When I run the code it converts to ascii characters. Btw i am just checking the code from break points. I saw ASCII characters from there.
Here is the code
String^ fileName = "file.txt";
FileStream^ fs = gcnew FileStream(fileName, FileMode::Open);
BinaryReader^ br = gcnew BinaryReader(fs);
INT32 tmpInd = 0;
array<Byte^>^ byteArr = gcnew array<Byte^>(br->BaseStream->Length);
while(br->BaseStream->Position < br->BaseStream->Length){
byteArr[tmpInd] = br->ReadByte();
tmpInd++;
}
fs->Close();

Read hex data from a file, starting at position x, terminating at first null byte (00)?

So I need to read a file that has a 'word' inside in hex (ACSII). Of course words can be of any length, but always starts at offset 0x1290. What I am trying to do is read the hex of a file starting at offset 0x1290, and continue UNTIL it encounters a null byte (00). So far all the coding I have tried seems to need a fixed length to read.
filePath = "C:\myfile"
BinaryReader reader = new BinaryReader(new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.None));
reader.BaseStream.Position = 0x1290; // The starting offset
byte[] word = reader.ReadBytes(); // Must specify length within ReadBytes(e.g. 0x99)
reader.Close();`
After the required 'word' there can often be other hex data which is not required, however there is always a null byte after the 'word'. This is why I cannot specify a length.

use while loop:
filePath = "C:\myfile"
BinaryReader reader = new BinaryReader(new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.None));
reader.BaseStream.Position = 0x1290;
byte char;
byte[] result=new byte[length_of_the_word];
int i=0;
while(((byte)char=reader.Read())!=-1)
{
result[i++]=char;
}
reader.close();
then replace -1 (end of file) with the end word hex, like 0x00

If you don't know how many chars is the length of your string you should use some kind of collection that doesn't require beforehand the exact length of data to store. This seems the perfect work for a List<byte>
List<byte> bits = new List<byte>();
using(FileStream s = new FileStream(#"C:\myfile", FileMode.Open))
using (BinaryReader reader = new BinaryReader(s))
{
reader.BaseStream.Position = 0x1290;
while (reader.PeekChar() != -1)
{
byte b = reader.ReadByte();
if(b != 0x00)
bits.Add(reader.ReadByte());
}
string result = Encoding.UTF8.GetString(bits.ToArray());
}

Thanks guys, I tried the above mentioned, but they seem to keep coming up with errors. Anyway I figured out a loop myself and am here to share:
int c = 0;
int runs = 0;
byte[] data = new byte[400]; // byte array setup
// read hex values (loop) and convert to acsii string
BinaryReader reader = new BinaryReader(new FileStream("C:\File", FileMode.Open, FileAccess.Read, FileShare.None));
reader.BaseStream.Position = 0x1290;
while (c == 0)
{
data[runs] = reader.ReadByte();
if (data[runs] == 0x00)
{
c = 1; // stop loop at .ReadByte = 0x00
}
runs++;
}
reader.Close();
// hex to acsii string, removing null bytes
result = Encoding.Default.GetString(data.Where(x => x != 0).ToArray());
Seems to work well

Convert file to binary in C#

I am trying to write a program that transfers a file through sound (kind of like a fax). I broke up my program into several steps:
convert file to binary
convert 1 to a certain tone and 0 to another
play the tones to another computer
other computer listens to tones
other computer converts tones into binary
other computer converts binary into file.
However, I can't seem to find a way to convert a file to binary. I found a way to convert a string to binary using
public static string StringToBinary(string data)
{
StringBuilder sb = new StringBuilder();
foreach (char c in data.ToCharArray())
{
sb.Append(Convert.ToString(c, 2).PadLeft(8,'0'));
}
return sb.ToString();
}
From http://www.fluxbytes.com/csharp/convert-string-to-binary-and-binary-to-string-in-c/ .
But I can't find out how to convert a file to binary (the file could be of any extension).
So, how can I convert a file to binary? Is there a better way for me to write my program?

Why don't you just open the file in binary mode?
this function opens the file in binary mode and returns the byte array:
private byte[] GetBinaryFile(filename)
{
byte[] bytes;
using (FileStream file = new FileStream(filename, FileMode.Open, FileAccess.Read))
{
bytes = new byte[file.Length];
file.Read(bytes, 0, (int)file.Length);
}
return bytes;
}
then to convert it to bits:
byte[] bytes = GetBinaryFile("filename.bin");
BitArray bits = new BitArray(bytes);
now bits variable holds 0,1 you wanted.
or you can just do this:
private BitArray GetFileBits(filename)
{
byte[] bytes;
using (FileStream file = new FileStream(filename, FileMode.Open, FileAccess.Read))
{
bytes = new byte[file.Length];
file.Read(bytes, 0, (int)file.Length);
}
return new BitArray(bytes);
}
Or even shorter code could be:
private BitArray GetFileBits(filename)
{
byte[] bytes = File.ReadAllBytes(filename);
return new BitArray(bytes);
}

Convert open xml string to byte[]

so, I am editing a word document, using OpenXML. And for some reasons, I convert it all into a string:
//conversion du byte en memorystream
using (var file = new MemoryStream(text))
using (var reader = new StreamReader(file))
{
WordprocessingDocument wordDoc = WordprocessingDocument.Open(file, true);
using (StreamReader sr = new StreamReader(wordDoc.MainDocumentPart.GetStream()))
{
docText = sr.ReadToEnd();
}
}
And then, I convert it as a byte.
But, a simple convert will not work:
byte[] back2Byte = System.Text.Encoding.ASCII.GetBytes(docText );
Because the string is a open xml string.
Tried this, but always got a corrupted file when I tried to open it with Word:
var repo = new System.IO.MemoryStream(System.Text.Encoding.UTF8.GetBytes(docText));
byte[] buffer = new byte[16 * 1024];
MemoryStream ms = new MemoryStream();
int read;
while ((read = repo.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, read);
}
byte[] back2Byte = ms.ToArray();
So, this doesn't work either:
byte[] back2Byte = new byte[docText.Length * sizeof(char)];
System.Buffer.BlockCopy(docText.ToCharArray(), 0, back2Byte, 0, back2Byte.Length);
edit : After some checkings, it seems it is write as a openxml document into the database, and so, word cannot read it. There is no error when i open it with notepad
How can I correct this?
So, the real issue is, how can I convert a OpenXML string to a byte that can be open in word?

You cannot do this sort of thing. You are getting the bytes for only one part of an OpenXML document. By definition, all Microsoft Office documents are multi-part OpenXML documents. You could theoretically capture the bytes for all the parts using a technique like you're currently using, but you would also have to capture all the part/relationship information necessary to reconstruct the multi-part document. You'd be better off just reading all the bytes of the file and storing them as-is:
// to read the file as bytes
var fileName = #"C:\path\to\the\file.xlsx";
var fileBytes = File.ReadAllBytes(fileName);
// to recreate the file from the bytes
File.WriteAllBytes(fileName, fileBytes)
If you need a string form of those bytes, try this:
// to convert bytes to a (non-readable) text form
var fileContent = Convert.ToBase64String(fileBytes);
// to convert base-64 back to bytes
var fileBytes = Convert.FromBase64String(fileContent);
Either way, there is absolutely no need to use the OpenXML SDK for your use case.

Original file bytes from StreamReader, magic number detection

I'm trying to differentiate between "text files" and "binary" files, as I would effectively like to ignore files with "unreadable" contents.
I have a file that I believe is a GZIP archive. I'm tring to ignore this kind of file by detecting the magic numbers / file signature. If I open the file with the Hex editor plugin in Notepad++ I can see the first three hex codes are 1f 8b 08.
However if I read the file using a StreamReader, I'm not sure how to get to the original bytes..
using (var streamReader = new StreamReader(#"C:\file"))
{
char[] buffer = new char[10];
streamReader.Read(buffer, 0, 10);
var s = new String(buffer);
byte[] bytes = new byte[6];
System.Buffer.BlockCopy(s.ToCharArray(), 0, bytes, 0, 6);
var hex = BitConverter.ToString(bytes);
var otherhex = BitConverter.ToString(System.Text.Encoding.UTF8.GetBytes(s.ToCharArray()));
}
At the end of the using statement I have the following variable values:
hex: "1F-00-FD-FF-08-00"
otherhex: "1F-EF-BF-BD-08-00-EF-BF-BD-EF-BF-BD-0A-51-02-03"
Neither of which start with the hex values shown in Notepad++.
Is it possible to get the original bytes from the result of reading a file via StreamReader?

Your code tries to change a binary buffer into a string. Strings are Unicode in NET so two bytes are required. The resulting is a bit unpredictable as you can see.
Just use a BinaryReader and its ReadBytes method
using(FileStream fs = new FileStream(#"C:\file", FileMode.Open, FileAccess.Read))
{
using (var reader = new BinaryReader(fs, new ASCIIEncoding()))
{
byte[] buffer = new byte[10];
buffer = reader.ReadBytes(10);
if(buffer[0] == 31 && buffer[1] == 139 && buffer[2] == 8)
// you have a signature match....
}
}

Usage (for a pdf file):
Assert.AreEqual("25504446", GetMagicNumbers(filePath, 4));
Method GetMagicNumbers:
private static string GetMagicNumbers(string filepath, int bytesCount)
{
// https://en.wikipedia.org/wiki/List_of_file_signatures
byte[] buffer;
using (var fs = new FileStream(filepath, FileMode.Open, FileAccess.Read))
using (var reader = new BinaryReader(fs))
buffer = reader.ReadBytes(bytesCount);
var hex = BitConverter.ToString(buffer);
return hex.Replace("-", String.Empty).ToLower();
}

You can't. StreamReader is made to read text, not binary. Use the Stream directly to read bytes. In your case FileStream.
To guess whether a file is text or binary you could read the first 4K into a byte[] and interpret that.
Btw, you tried to force chars into bytes. This is invalid by principle. I suggest you familiarize yourself with what an Encoding is: it is the only way to convert between chars and bytes in a semantically correct way.