Develop Reference

Converting byte[] to Image C# (ArgumentException Error)

(I use Google Translate, sorry..)
I'm trying to do a small project with shorthand.
I found similar topics, but they are not what I need.
The bottom line is, I get an image at the input, convert it to byte [], then to binary. (Everything is OK here)
Then I translate the text to binary. (Everything is OK here)
in the binary array, I change the last two bits to the ones I need.
I translate everything back to byte[] (everything is OK Here)
and then I try to convert byte[] to Image and an error occurs (Incorrect argument)
If I do not make changes to binary, the conversion is successful ( and I get the same image that I gave at the input).
change code in the binary array:
public byte[] ShifrMessage(byte[] input, string message)
{
byte[] ConvertToByteArray(string str, Encoding encoding)
{
return encoding.GetBytes(str);
}
String ToBinary(Byte[] data)
{
return string.Join("", data.Select(byt => Convert.ToString(byt, 2).PadLeft(8, '0')));
}
//message in the binary
var binaryString = ToBinary(ConvertToByteArray(message, Encoding.ASCII));
byte[] ret = new byte[input.Length];
for (int i = 0; i < ret.Length; i++)
{
string a = Convert.ToString(ret[i], 2).PadLeft(8, '0');
//changing the last two bits
if (binaryString.Length >= 2)
{
a = a.Substring(0, a.Length - 2) + binaryString.Substring(0, 2);
binaryString = binaryString.Substring(2);
}
///
byte b = StringToByte(a);
ret[i] = b;
}
return ret;
}
I assume that when converting to Image, the integrity of the image that was changed is checked.
conversion:
public Image byteArrayToImage(byte[] byteArrayIn)
{
using (var ms1 = new MemoryStream(byteArrayIn))
{
return Image.FromStream(ms1);
}
}
Can you tell me what the problem might be?

C# Convert HEX (Korean) To Korean Letters

I have a Hex string that I am converting into characters. This is the function I am using.
public string GetAsciiString(bool replaceNewline = true)
{
char[] chars = new char[data.Length + 1];
byte[] bytes = new byte[data.Length + 1];
bytes[0] = opcode;
Array.Copy(data, 0, bytes, 1, data.Length);
for (int i = 0; i < bytes.Length; ++i)
{
byte value = bytes[i];
if ((value == '\n' || value == '\r') && !replaceNewline)
chars[i] = (char)value;
else if (value < 32 || value > 126)
chars[i] = '.';
else chars[i] = (char)value;
}
return new string(chars);
}
However this only displays english characters and not korean. Any idea on how I can get it to display Korean?
Edit: I see the issue was that I was converting to Ascii.

Okay, there are multiple ways to go at this.
The operation to turn byte arrays into strings is known as decoding. In .NET, this is done with the Encoding class. In your case, you must first find the corresponding encoding. Looking at the documentation linked above, encoding ks_c_5601-1987 corresponds to code page 949, so:
var encoding = Encoding.GetEncoding(949);
Once you have that encoding, you can use it to decode the bytes:
var text = encoding.GetString(bytes);
This leaves the matter of those bytes. If you already have a byte array, you're good to go. If you have a hex string, I suggest you look into existing questions for this, for instance: https://stackoverflow.com/a/311165/.
If your data is in a stream, I recommend you use a StreamReader for this instead:
using(var reader = new StreamReader(stream, encoding)) // use encoding to decode from stream
{
var text = reader.ReadToEnd();
}

How to read blob data from MySQL in c# [duplicate]

I have a byte[] array that is loaded from a file that I happen to known contains UTF-8.
In some debugging code, I need to convert it to a string. Is there a one-liner that will do this?
Under the covers it should be just an allocation and a memcopy, so even if it is not implemented, it should be possible.

string result = System.Text.Encoding.UTF8.GetString(byteArray);

There're at least four different ways doing this conversion.
Encoding's GetString, but you won't be able to get the original bytes back if those bytes have non-ASCII characters.
BitConverter.ToString The output is a "-" delimited string, but there's no .NET built-in method to convert the string back to byte array.
Convert.ToBase64String You can easily convert the output string back to byte array by using Convert.FromBase64String. Note: The output string could contain '+', '/' and '='. If you want to use the string in a URL, you need to explicitly encode it.
HttpServerUtility.UrlTokenEncodeYou can easily convert the output string back to byte array by using HttpServerUtility.UrlTokenDecode. The output string is already URL friendly! The downside is it needs System.Web assembly if your project is not a web project.
A full example:
byte[] bytes = { 130, 200, 234, 23 }; // A byte array contains non-ASCII (or non-readable) characters
string s1 = Encoding.UTF8.GetString(bytes); // ���
byte[] decBytes1 = Encoding.UTF8.GetBytes(s1); // decBytes1.Length == 10 !!
// decBytes1 not same as bytes
// Using UTF-8 or other Encoding object will get similar results
string s2 = BitConverter.ToString(bytes); // 82-C8-EA-17
String[] tempAry = s2.Split('-');
byte[] decBytes2 = new byte[tempAry.Length];
for (int i = 0; i < tempAry.Length; i++)
decBytes2[i] = Convert.ToByte(tempAry[i], 16);
// decBytes2 same as bytes
string s3 = Convert.ToBase64String(bytes); // gsjqFw==
byte[] decByte3 = Convert.FromBase64String(s3);
// decByte3 same as bytes
string s4 = HttpServerUtility.UrlTokenEncode(bytes); // gsjqFw2
byte[] decBytes4 = HttpServerUtility.UrlTokenDecode(s4);
// decBytes4 same as bytes

A general solution to convert from byte array to string when you don't know the encoding:
static string BytesToStringConverted(byte[] bytes)
{
using (var stream = new MemoryStream(bytes))
{
using (var streamReader = new StreamReader(stream))
{
return streamReader.ReadToEnd();
}
}
}

Definition:
public static string ConvertByteToString(this byte[] source)
{
return source != null ? System.Text.Encoding.UTF8.GetString(source) : null;
}
Using:
string result = input.ConvertByteToString();

Converting a byte[] to a string seems simple, but any kind of encoding is likely to mess up the output string. This little function just works without any unexpected results:
private string ToString(byte[] bytes)
{
string response = string.Empty;
foreach (byte b in bytes)
response += (Char)b;
return response;
}

I saw some answers at this post and it's possible to be considered completed base knowledge, because I have a several approaches in C# Programming to resolve the same problem. The only thing that is necessary to be considered is about a difference between pure UTF-8 and UTF-8 with a BOM.
Last week, at my job, I needed to develop one functionality that outputs CSV files with a BOM and other CSV files with pure UTF-8 (without a BOM). Each CSV file encoding type will be consumed by different non-standardized APIs. One API reads UTF-8 with a BOM and the other API reads without a BOM. I needed to research the references about this concept, reading the "What's the difference between UTF-8 and UTF-8 without BOM?" Stack Overflow question, and the Wikipedia article "Byte order mark" to build my approach.
Finally, my C# Programming for both UTF-8 encoding types (with BOM and pure) needed to be similar to this example below:
// For UTF-8 with BOM, equals shared by Zanoni (at top)
string result = System.Text.Encoding.UTF8.GetString(byteArray);
//for Pure UTF-8 (without B.O.M.)
string result = (new UTF8Encoding(false)).GetString(byteArray);

Using (byte)b.ToString("x2"), Outputs b4b5dfe475e58b67
public static class Ext {
public static string ToHexString(this byte[] hex)
{
if (hex == null) return null;
if (hex.Length == 0) return string.Empty;
var s = new StringBuilder();
foreach (byte b in hex) {
s.Append(b.ToString("x2"));
}
return s.ToString();
}
public static byte[] ToHexBytes(this string hex)
{
if (hex == null) return null;
if (hex.Length == 0) return new byte[0];
int l = hex.Length / 2;
var b = new byte[l];
for (int i = 0; i < l; ++i) {
b[i] = Convert.ToByte(hex.Substring(i * 2, 2), 16);
}
return b;
}
public static bool EqualsTo(this byte[] bytes, byte[] bytesToCompare)
{
if (bytes == null && bytesToCompare == null) return true; // ?
if (bytes == null || bytesToCompare == null) return false;
if (object.ReferenceEquals(bytes, bytesToCompare)) return true;
if (bytes.Length != bytesToCompare.Length) return false;
for (int i = 0; i < bytes.Length; ++i) {
if (bytes[i] != bytesToCompare[i]) return false;
}
return true;
}
}

There is also class UnicodeEncoding, quite simple in usage:
ByteConverter = new UnicodeEncoding();
string stringDataForEncoding = "My Secret Data!";
byte[] dataEncoded = ByteConverter.GetBytes(stringDataForEncoding);
Console.WriteLine("Data after decoding: {0}", ByteConverter.GetString(dataEncoded));

In addition to the selected answer, if you're using .NET 3.5 or .NET 3.5 CE, you have to specify the index of the first byte to decode, and the number of bytes to decode:
string result = System.Text.Encoding.UTF8.GetString(byteArray, 0, byteArray.Length);

Alternatively:
var byteStr = Convert.ToBase64String(bytes);

The BitConverter class can be used to convert a byte[] to string.
var convertedString = BitConverter.ToString(byteAttay);
Documentation of BitConverter class can be fount on MSDN.

To my knowledge none of the given answers guarantee correct behavior with null termination. Until someone shows me differently I wrote my own static class for handling this with the following methods:
// Mimics the functionality of strlen() in c/c++
// Needed because niether StringBuilder or Encoding.*.GetString() handle \0 well
static int StringLength(byte[] buffer, int startIndex = 0)
{
int strlen = 0;
while
(
(startIndex + strlen + 1) < buffer.Length // Make sure incrementing won't break any bounds
&& buffer[startIndex + strlen] != 0 // The typical null terimation check
)
{
++strlen;
}
return strlen;
}
// This is messy, but I haven't found a built-in way in c# that guarentees null termination
public static string ParseBytes(byte[] buffer, out int strlen, int startIndex = 0)
{
strlen = StringLength(buffer, startIndex);
byte[] c_str = new byte[strlen];
Array.Copy(buffer, startIndex, c_str, 0, strlen);
return Encoding.UTF8.GetString(c_str);
}
The reason for the startIndex was in the example I was working on specifically I needed to parse a byte[] as an array of null terminated strings. It can be safely ignored in the simple case

A LINQ one-liner for converting a byte array byteArrFilename read from a file to a pure ASCII C-style zero-terminated string would be this: Handy for reading things like file index tables in old archive formats.
String filename = new String(byteArrFilename.TakeWhile(x => x != 0)
.Select(x => x < 128 ? (Char)x : '?').ToArray());
I use '?' as the default character for anything not pure ASCII here, but that can be changed, of course. If you want to be sure you can detect it, just use '\0' instead, since the TakeWhile at the start ensures that a string built this way cannot possibly contain '\0' values from the input source.

Try this console application:
static void Main(string[] args)
{
//Encoding _UTF8 = Encoding.UTF8;
string[] _mainString = { "Hello, World!" };
Console.WriteLine("Main String: " + _mainString);
// Convert a string to UTF-8 bytes.
byte[] _utf8Bytes = Encoding.UTF8.GetBytes(_mainString[0]);
// Convert UTF-8 bytes to a string.
string _stringuUnicode = Encoding.UTF8.GetString(_utf8Bytes);
Console.WriteLine("String Unicode: " + _stringuUnicode);
}

Here is a result where you didn’t have to bother with encoding. I used it in my network class and send binary objects as string with it.
public static byte[] String2ByteArray(string str)
{
char[] chars = str.ToArray();
byte[] bytes = new byte[chars.Length * 2];
for (int i = 0; i < chars.Length; i++)
Array.Copy(BitConverter.GetBytes(chars[i]), 0, bytes, i * 2, 2);
return bytes;
}
public static string ByteArray2String(byte[] bytes)
{
char[] chars = new char[bytes.Length / 2];
for (int i = 0; i < chars.Length; i++)
chars[i] = BitConverter.ToChar(bytes, i * 2);
return new string(chars);
}

string result = ASCIIEncoding.UTF8.GetString(byteArray);

How to read mixed file of byte and string

I've a mixed file with a lot of string line and part of byte encoded data.
Example:
--Begin Attach
Content-Info: /Format=TIF
Content-Description: 30085949.tif (TIF File)
Content-Transfer-Encoding: binary; Length=220096
II*II* Îh ÿÿÿÿÿÿü³küìpsMg›Êq™Æ™Ôd™‡–h7ÃAøAú áùõ=6?Eã½/ô|û ƒú7z:>„Çÿý<þ¯úýúßj?å¿þÇéöûþ“«ÿ¾ÁøKøÈ%ŠdOÿÞÈ<,Wþ‡ÿ·ƒïüúCÿß%Ï$sŸÿÃÿ÷‡þåiò>GÈù#ä|‘ò:#ä|Š":#¢:;ˆèŽˆèʤV‘ÑÑÑÑÑÑÑÑÑçIþ×o(¿zHDDDDDFp'.Ñ:ˆR:aAràÁ¬LˆÈù!ÿÿï[ÿ¯Äàiƒ"VƒDÇ)Ê6PáÈê$9C”9C†‡CD¡pE#¦œÖ{i~Úý¯kköDœ4ÉU”8`ƒt!l2G
--End Attach--
i try to read file with streamreader:
string[] lines = System.IO.File.ReadAllLines(#"C:\Users\Davide\Desktop\20041230000D.xmm")
I read line by line the file, and when line is equal "Content-Transfer-Encoding: binary; Length=220096", i read all following lines and write a "filename"(in this case 30085949.tif) file.
But i'm reading strings, not byte data and result file is damaged (now i try with tiff file). Any suggestion for me?
SOLUTION
Thanks for reply. I've adopted this solution: I builded a LineReader extend BinaryReader:
public class LineReader : BinaryReader
{
public LineReader(Stream stream, Encoding encoding)
: base(stream, encoding)
{
}
public int currentPos;
private StringBuilder stringBuffer;
public string ReadLine()
{
currentPos = 0;
char[] buf = new char[1];
stringBuffer = new StringBuilder();
bool lineEndFound = false;
while (base.Read(buf, 0, 1) > 0)
{
currentPos++;
if (buf[0] == Microsoft.VisualBasic.Strings.ChrW(10))
{
lineEndFound = true;
}
else
{
stringBuffer.Append(buf[0]);
}
if (lineEndFound)
{
return stringBuffer.ToString();
}
}
return stringBuffer.ToString();
}
}
Where Microsoft.VisualBasic.Strings.ChrW(10) is a Line Feed.
When i parse my file:
using (LineReader b = new LineReader(File.OpenRead(path), Encoding.Default))
{
int pos = 0;
int length = (int)b.BaseStream.Length;
while (pos < length)
{
string line = b.ReadLine();
pos += (b.currentPos);
if (!beginNextPart)
{
if (line.StartsWith(BEGINATTACH))
{
beginNextPart = true;
}
}
else
{
if (line.StartsWith(ENDATTACH))
{
beginNextPart = false;
}
else
{
if (line.StartsWith("Content-Transfer-Encoding: binary; Length="))
{
attachLength = Convert.ToInt32(line.Replace("Content-Transfer-Encoding: binary; Length=", ""));
byte[] attachData = b.ReadBytes(attachLength);
pos += (attachLength);
ByteArrayToFile(#"C:\users\davide\desktop\files.tif", attachData);
}
}
}
}
}
I read a byte length from file and i read following n bytes.

Your problem here is that a StreamReader assumes that it is the only thing reading the file, and as a result it reads ahead. Your best bet is to read the file as binary and use the appropriate text encoding to retrieve the string data out of your own buffer.
Since apparently you don't mind reading the entire file into memory, you can start with a:
byte[] buf = System.IO.File.ReadAllBytes(#"C:\Users\Davide\Desktop\20041230000D.xmm");
Then assuming you're using UTF-8 for your text data:
int offset = 0;
int binaryLength = 0;
while (binaryLength == 0 && offset < buf.Length) {
var eolIdx = Array.IndexOf(offset, 13); // In a UTF-8 stream, byte 13 always represents newline
string line = System.Text.Encoding.UTF8.GetString(buf, offset, eolIdx - offset - 1);
// Process your line appropriately here, and set binaryLength if you expect binary data to follow
offset = eolIdx + 1;
}
// You don't necessarily need to copy binary data out, but just to show where it is:
var binary = new byte[binaryLength];
Buffer.BlockCopy(buf, offset, binary, 0, binaryLength);
You might also want to do a line.TrimEnd('\r'), if you expect Window-style line endings.

C# Encoding Conversion

I have an encrypt routine in c++, I translate this to C#:
example:
public void main()
{
string myPwd = "ÖFÖæ6";
string pwdCoded = XEncrypt.EncryptData_Patch_x_Net(myPwd);
//Result OK: ÖFÖæ–6
}
public static string EncryptData_Patch_x_Net(string Data)
{
byte[] bytes = new byte[Data.Length];
for (int n = 0; n < Data.Length; n++)
{
bytes[n] = (byte)Data[n];
}
System.Text.Encoding MyEncoding = System.Text.Encoding.Default;
String MyResult = MyEncoding.GetString(bytes);
return MyResult;
}
I need to make the inverse routine that made it convert from:
ÖFÖæ–6 to ÖFÖæ6 (notice there's a dash in the left string)
I did this last function, but erroneously performs the encoding
public static string DecryptData_Patch_x_Net(string Data)
{
byte[] bytes = new byte[Data.Length];
for (int n = 0; n < Data.Length; n++)
{
bytes[n] = (byte)Data[n];
}
System.Text.Encoding MyEncoding = System.Text.Encoding.GetEncoding(1252);
String MyResult = MyEncoding.GetString(bytes);
return MyResult;
}

This is not encryption and you are seriously complicating what it actually is.
Encoding iso88591 = Encoding.GetEncoding(28591);
Encoding w1252 = Encoding.GetEncoding(1252);
//
string pwd = "ÖFÖæ\u00966"; //The SPA control character will not survice a Stackoverflow post
//So I use \u0096 to represent it
string result = w1252.GetString(iso88591.GetBytes(pwd)); //"ÖFÖæ–6"
string original = iso88591.GetString(w1252.GetBytes(result)); //"ÖFÖæ6" with the hidden control character before 6
Console.WriteLine(result == "ÖFÖæ–6"); //True
Console.WriteLine(original == "ÖFÖæ\u00966"); //True

Your misnamed ...Encrypt... function makes a fundamental error. You take a string, which treat as a char[] (thats fine), then explicitly cast each char to a byte. That is a narrowing conversion. You'll lose any of the high bits and the ability to round trip more unusual chars. If you look at this question it should help to understand.
You could use this function to get the bytes without loss of information,
static byte[] GetBytes(string str)
{
byte[] bytes = new byte[str.Length * sizeof(char)];
System.Buffer.BlockCopy(str.ToCharArray(), 0, bytes, 0, bytes.Length);
return bytes;
}
The byte array will round trip on systems that share endianess.
As Esailija states, becuase its simple and it will explicitly return little endian results, you're better off calling
byte[] Encoding.Unicode.GetBytes(string)
To achieve the same.