Develop Reference

Persisting text as byte array to flat file

Update
This is to hide my public key on the client side to make it slightly more difficult for prying eyes to get to it. Yes I know the intent of the public key is to stay public but I am trying to mitigate key substitution attacks and in addition to obfuscation, assembly merging, assembly signing and some other measures this is a part of the overall strategy. So in my code that gets shipped to the client side I want to be able to do something like this
string publicKey = #"random characters" //don't want this in the code
byte[] keyBytes = [............] //this should be in the code
I am not quite sure how do I take the text of my public key, convert it to a byte array and then use that in the client code to convert back into public key.
I reckon there is an easy way to do this but I am going round in circles trying to figure it out.
Essentially I have a series of text data which I want to be able to save as bytes to a flat file. I can read it as a byte array but when I use a BinaryWriter to write that byte array to a file I end up with the original text.
Can someone please help?

Just as every file, a text file is a binary file.
It just happens to be that in this case every binary number corresponds with a character, so when you open the file in a text editor, you see readable text.
Obligatory The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!).

You could create a little converter for this purpose.
string publicKey = "AsdfsSDhysffsdfsdfZ09";
Console.Write("byte[] keyBytes = { ");
Console.Write(String.Join(", ", Array.ConvertAll(Encoding.ASCII.GetBytes(publicKey), b => String.Format("0x{0:X2}", b))));
Console.WriteLine("};");
Run it. Then just copy the last line of the output to your source code.

Converting Binary Data to String [In Persian]

I am working on a system that needs to read a binary file containing certain Persian names/stock instruments. I need to convert the binary data into string to be used in further processes. I have googled it and haven't really found a solution to my problem. Anyone here who has worked in such a scenario or knows how to tackle such a problem?
Here is the code that I am using to convert the bytes to string (simple as it maybe):
byte[] data = binaryReader.ReadBytes(amountOfData);
string symbolRead = Encoding.ASCII.GetString(data);
FYI, I have tried to change my system locale to Persian and that hasn't helped either. Although it does allow me to view already written text in Persian.
Hoping to find a solution.
Thanks.

Don't use ASCII for encoding. First try using Default after setting your locale; then try asking directly someone what encoding is most used for Persia, and use this one.

Determine what coding is used in your file and use the corresponding encoding instead of Encoding.ASCII.GetString(...). Possible values could be Encoding.UTF8.GetString(...) or Encoding.Default.GetString(...) to use your system encoding. See documentation of the Encoding class for other possibilities.

Why binary data writing's result is string?

I want to create a binary file and store string data in it, I used this sample:
FileStream fs = new FileStream("c:\\test.data", FileMode.Create);
BinaryWriter bw = new BinaryWriter(fs);
bw.Write(Encoding.ASCII.GetBytes("david stein"));
bw.Close();
but when I opened created file by this sample (test.data) in notepad, it has string data in it ("david stein"), now my question is that whats the difference between this binary writing and text writing when the result is string?
I'm looking to create a data in binary file until user can not open and read my data by note pad and if user open it in notepad see real binary data .
in some files when you open theme in text editors you can not read file content like jpg files contents,they do not use any encryption methods,what about it?how can i wite my data like this?

now my question is that whats the difference between this binary writing and text writing when the result is string?
The data in a file is always "a sequence of bytes". In this case, the sequence of bytes you've written is "the bytes representing the text 'david stein'" in the ASCII encoding. So yes, if you open the file in any editor which tries to interpret the bytes as text in a way which is compatible with ASCII, you'll see the text "david stein". Really it's just a load of bytes though - it all depends on how you interpret them.
If you'd written:
File.WriteAllText("c:\\test.data", "david stein", Encoding.ASCII);
you'd have ended up with the exact same sequence of bytes. There are any number of ways you could have created a file with the same bytes in. There's nothing about File.WriteAllText which "marks" the file as text, and there's nothing about FileStream or BinaryWriter which marks the file as binary.
EDIT: From comments:
I'm looking to create a data in binary file until user can not open and read my data by note pad
Well, there are lots of ways of doing that with different levels of security. Ideally, you'd want some sort of encryption - but then the code reading the data would need to be able to decrypt it as well, which means it would need to be able to get a key. That then moves the question to "how do I store a key".
If you only need to verify the data in the file (e.g. check that it matches something from elsewhere) then you could use a cryptographic hash instead.
If you only need to prevent the most casual of snoopers, you could use something which is basically just obfuscation - a very weak form of encryption with no "key" as such. Anyone who dceompiled your code would easily be able to get at the data in that case, but you may not care too much about that.
It all depends on your requirements.

All data is binary. A text file is binary data that happens to be a limited subset that represent valid characters, but it's still binary.
The way text editors typically differentiate a text file from a binary file is they scan a certain portion of the file for zero values, \0. These never exist in text-only files and almost always exist in binary files.

C#: Converting byte[] to UTF8 encoded string

I am using a library called EXIFextractor to extract metadata information from images. This lib in part is using System.Drawing.Imaging.PropertyItem to do all the hard work. Some of the data in PropertyItem, such as Image Details etcetera, are fetched as an ASCII-string stored in a byte[] according to the Microsoft documentation.
My problem is that international characters (å, ä, ö, etcetera) are dropped and replaced by questionmarks. When I debug the code it is apparent that the byte[] is a representation of an UTF-8.
I'd like to parse the byte[] as an UTF8-string, how can I do this without loosing any information in the process?
Thanks in advance!
Update:
I have been asked to provide a snippet from my code:
The first snippet is from the class I use, namely the EXIFextractor.cs written by Asim Goheer
foreach( System.Drawing.Imaging.PropertyItem p in parr )
{
string v = "";
// ...
else if( p.Type == 0x2 )
{
// string
v = ascii.GetString(p.Value);
}
And this is my code where I try my best to handle the results of the above.
try {
EXIFextractor exif = new EXIFextractor(ref bmp, "");
object o;
if ((o = exif["Image Description"]) != null)
MediaFile.Description = Tools.UTF8Encode(o.ToString());
I have also tried a couple of other ways of getting my precious å, ä, ö from the data, but nothing seems to do the trick. I am starting to think Hans Passant is right about his conclusions in his answer below.

string yourText = System.Text.Encoding.UTF8.GetString(yourByteArray);

Use the GetString method on the Encoding.UTF8 object.

Yes, this is a problem with the app or camera that originated the image. The EXIF standard has horrible support for text, it has to be encoded in ASCII. That only ever works out well when the photographer speaks English. No doubt the software that encoded the image is ignoring this requirement. Which is what the PropertyItem class is doing as well, it encodes a string to byte[] with Marshal.StringToHGlobalAnsi(), which assumes the system's default code page.
There's no obvious fix for this, you'll get mojibake when the photo was made too far away from your machine.

Maybe you could try another encoding? UTF16, Unicode?
If you aren't sure if it got encodes right in the first place try to view the exif metadata with another exif reader.

How do you write byte[] array using log4.net

I have a byte[] with some data in it, I would like to write this byte array AS-IS to the log file using log4.net. The problems that i am facing is that
There are no overload for byte[] in TextWriter, so even implementing an IObjectRenderer is of no use.
I dont have access to the underlying Stream object of Log4.net
Also tried converting byte[] into char[] still when i write it, it adds an extra byte.
Is this even possible with Log4.net.
Thanx in Advance.

Log files are usually plain text files. It's probably best to log your byte array represented as string.
Have a look at BitConverter.ToString or Convert.ToBase64String.

Nope. Have you thought about writing it out as a hex string (see this post)?

I also think that logging any larger data is kind of useless, however, i guess this is what you are looking for - this converts your bytes to string.
System.Text.Encoding.ASCII.GetString(byteArray)
I believe you can figure out how to use that for logging.
Pz, the TaskConnect developer

If you are logging into DB then use Binary type with maximum size