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

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

Related

Adding Int32 to List<byte> using AddRange throwing exception despite being successful

I'm creating an application that will take an image in a certain format from one of a video game's files and convert it to a DDS. This requires me to build the DDS in a buffer and then write it out to a DDS file. This buffer is of type List<byte>.
I first write the magic number, which is just the text "DDS ", with this code:
ddsFile.AddRange(Encoding.ASCII.GetBytes("DDS "));
I then need to write the header size, which is always 0x7C000000 (124), and this is where I've hit a wall. I used this code to write it to the buffer:
ddsFile.AddRange(BitConverter.GetBytes(0x0000007C));
This made sense to me because Encoding.ASCII.GetBytes()says itself that it returns a byte[], and it does accept an int as a parameter, no problem. And additionally, this was what I saw recommended when looking for a method for adding multi-byte values to a byte list. But for whatever reason, when the program tries to execute that line, this exception is thrown:
Unable to cast object of type 'System.Byte[]' to type 'System.IConvertible'.
But what's even more strange to the point of being ridiculous is that, upon seeing what did make it into the buffer, I see that the int actually was being written to the buffer, but the exception was still occurring for who knows what reason.
Bizarrely, even writing a single byte to the list after writing the magic number e.g. ddsFile.Add((byte)0x00)); results in the same thing.
Any help in figuring out why this exception occurs and/or a solution would be greatly appreciated.
This is not an answer to the question but a suggestion to do it differently.
Instead of using a List<byte> and manually doing all the conversions (while certainly possible, it's cumbersome), use a stream and a BinaryWriter - the stream can be a memory stream if you want to buffer the image in memory or a file stream if you want to write it to disk right away.
Using a BinaryWriter against the stream makes the conversions a lot simpler (and you can still manually convert parts of the data easily, if you need to do so).
Here's a short example:
var ms = new MemoryStream();
var bw = new BinaryWriter(ms, Encoding.ASCII);
bw.Write("DDS ");
bw.Write(124); // writes 4 bytes
bw.Write((byte) 124); // writes 1 byte
...
Use whichever overload of Write() you need to output the right bytes. (This short example omits cleaning up things but if you use a file stream, you'll need to make sure that you properly close it.)

Fastest way to serialize C# object array into string

I am looking for the fastest way to serialize and deserialize a C# array of objects into a string...
Why a string and not a byte array? Well, I am working with a networking system (The Unity3d networking system to be specific) and they have placed a rather annoying restriction which does not allow the sending of byte arrays or custom types, two things I need (hard to explain my situation).
The simplest solution I have come up with for this is to serialize my custom types into a string, and then transmit that string as opposed to directly sending the object array.
So, that is the question! What is the fastest way to serialize an object array into a string? I would preferably like to avoid using voodoo characters (invisible/special characters), as I am not sure if Unity3d will cull them, but base64 encoding doesn't take full advantage of the allowed character spectrum. I am also worried about the efficiency of using base 64.
Obviously, since this is networking related, having the serialized data be as small as possible is a plus.
EDIT:
One possible way to do this would be to serialize to a byte array, and then pretend that that byte array is a string. The problem is, I am afraid that .Net 2.0, or Unity's networking system will end up culling some of the special or invisible characters created using this method... Something which very much needs to be avoided. I am hoping for a solution that has near or equal speed to this, but does not use any of the characters that are likely to be culled. (I have no idea what characters these are, but I have had bad experiences with Unity when it came to direct conversions to strings from byte arrays)
Json.Net is what I always use its simple and gets the job done in a human readable way. Json is about as lightweight as it gets and is widely used for sending data over the wire.
I'll give you this answer as accepted, but I suggest adding base64 encoding to your answer!
–Georges Oates Larsen
Thank you, and yes that is also a great option if readability is not an issue.
We use SoapFormatter so that the object be embedded in Javascript variables and otherwise be "safe" to pass around:
using (MemoryStream oStream = new MemoryStream())
{
(new SoapFormatter()).Serialize(oStream, theObject);
return Encoding.Default.GetString(oStream.ToArray());
}
using(MemoryStream s = new MemoryStream()) {
new BinaryFormatter().Serialize(s, obj);
return Convert.ToBase64String(s.ToArray());
}
and
using(MemoryStream s = new MemoryStream(Convert.FromBase64String(str))) {
return new BinaryFormatter().Deserialize(s);
}

How to specify BinaryReader to interpret as big-endian

Is there a way to tell the BinaryReader to interpret as big-endian? Like just saying "interpret everything big endian" so I don't have to write extra code to manually read in bytes, reverse them, and then convert it to int or float or whatever I need.
UPDATE
looked around, seems like you can't.
Which is kind of strange; I figured it's something you'd naturally do when writing a class that will read binary data from arbitrary files.
Try creating a BinaryReader BinaryReader(stream,encoding) using the Encoding.BigEndianUnicode Property
Since it was pointed out that this is for text only, you will have to create your own code to manually convert it, or you can use Scott Chamberlain's example at the end of this MSDN Forum Posting .

How many bits does BinaryReader.PeekChar() read?

I am working on improving a stream reader class that uses a BinaryReader. It consists of a while loop that uses .PeekChar() to check if more data exists to continue processing.
The very first operation is a .ReadInt32() which reads 4 bytes. What if PeekChar only "saw" one byte (or one bit)? This doesn't seem like a reliable way of checking for EOF.
The BinaryReader is constructed using its default parameters, which as I understand it, uses UTF8 as the default encoding. I assume that .PeekChar() checks for 8 bits but I really am not sure.
How many bits does .PeekChar() look for? (and what are some alternate methods to checking for EOF?)
Here BinaryReader.PeekChar
I read:
ArgumentException: The current character cannot be decoded into the
internal character buffer by using the Encoding selected for the
stream.
This makes clear that amount of memory read depends on Encoding applied to that stream.
EDIT
Actually definition according to MSDN is:
Returns the next available character and does not advance the
byte or character position.*
Infact, it depends on encoding if this is a byte or more...
Hope this helps.
Making your Read*() calls blindly and handling any exceptions that are thrown is the normal method. I don't believe that the stream position is moved if anything goes wrong.
The PeekChar() method of BinaryReader is very buggy. Even when trying to read a from a memory stream with UTF8 encoded data, PeekChar() throws an exception after reading a particular length of the stream. The BCL team has acknowledged the issue, but they have not committed to resolving the issue. Their only response is to avoid using PeekChar() if you can.

parsing binary file in C#

I have a binary file. i stored it in byte array. file size can be 20MB or more. then i want to parse or find particular value in the file. i am doing it by 2 ways ->
1. By converting full file in char array.
2. By converting full file in hex string.(i also have hex values)
what is best way to parse full file..or should i do in binary form. i am using vs-2005.
From the aspect of memory consumption, it would be best it you could parse it directly, on-the-fly.
Converting it to a char array in C# means effectively doubling it's size in memory (presuming you are converting each byte to a char), while hex string will take at least 4 times the size (C# chars are 16-bit unicode characters).
On the other hand, it you need to make many searches and parsing over an existing set of data repeatedly, you may benefit from having it stored in any form which suits your needs better.
What's stopping you from seaching in the byte[]?
IMHO, If you're simply searching for a byte of specified value, or several continous bytes, this is the easiest way and most efficient way to do it.
If I understood your question correctly you need to find strings which can contain any characters in a large binary file. Does the binary file contain text? If so do you know the encoding? If so you can use StreamReader class like so:
using (StreamReader sr = new StreamReader("C:\test.dat", System.Text.Encoding.UTF8))
{
string s = sr.ReadLine();
}
In any case I think it's much more efficient using some kind of stream access to the file, instead of loading it all to memory.
You could load it by chunks into the memory, and then use some pattern matching algorithm (like Knuth-Moris-Pratt or Karp-Rabin)

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