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CRC-16/ARC from String in vb.net

I have the c# code below
public string CRCCalculator(string dtc)
{
ushort crc = 0x0000;
byte[] data = GetBytesFromHexString(dtc);
for (var pos = 0; pos < data.Length; pos++)
{
crc ^= data[pos];
for (var i = 8; i != 0; i--)
{
if ((crc & 0x0001) != 0)
{
crc >>= 1;
crc ^= 0xA001;
}
else
crc >>= 1;
}
}
return crc.ToString("X4");
}
But I need this in vb.net, I have personally tried converting it and I have converted plenty of c# code to vb.net in the past however I have not worked with ushort's and bits and such.
Here is the converted VB.net code:
Public Shared Function CRCCalculator(dtc As String) As String
Dim crc As UShort = &H0
Dim data As Byte() = getBytesFromHexString(dtc)
Dim pos = 0
Do While (pos < data.Length)
crc ^= data(pos)
Dim i = 8
Do While (i <> 0)
i = (i - 1)
If (crc And &H1) <> 0 Then
crc >>= 1
crc ^= &HA001
Else
crc >>= 1
End If
Loop
pos = (pos + 1)
Loop
Return crc.ToString("X4")
End Function
Instead of getting a value back I always get 0.

I don't think "^" does what you think it does. Use "Xor" instead.
C# ^ operator reference - exclusive-or operator
VB ^ operator reference - power-of/exponent operator

Hex Dump EXE File

How do I properly display the contents of an EXE file "C:/Path/To/File.exe" in hexadecimal form? So far, I have:
byte[] BytArr = File.ReadAllBytes("C:/Path/To/File.exe")
I tried using a switch statement (not shown here) that reads every few bytes and should output the appropriate hexadecimal code, but it failed. What should I do? I would really appreciate it if anyone can help me.
Beware that the answer code isn't well formatted and is rather inefficient (source: https://www.codeproject.com/articles/36747/quick-and-dirty-hexdump-of-a-byte-array), but I did make an effort to format it properly.
Answer Code:
using System.Text;
namespace HexDump
{
class Utils
{
public static string HexDump(byte[] bytes, int bytesPerLine = 16)
{
if (bytes == null) return "<null>";
int bytesLength = bytes.Length;
char[] HexChars = "0123456789ABCDEF".ToCharArray();
int firstHexColumn =
8 // 8 characters for the address
+ 3; // 3 spaces
int firstCharColumn = firstHexColumn
+ bytesPerLine * 3 // - 2 digit for the hexadecimal value and 1 space
+ (bytesPerLine - 1) / 8 // - 1 extra space every 8 characters from the 9th
+ 2; // 2 spaces
int lineLength = firstCharColumn
+ bytesPerLine // - characters to show the ascii value
+ Environment.NewLine.Length; // Carriage return and line feed (should normally be 2)
char[] line = (new String(' ', lineLength - Environment.NewLine.Length) + Environment.NewLine).ToCharArray();
int expectedLines = (bytesLength + bytesPerLine - 1) / bytesPerLine;
StringBuilder result = new StringBuilder(expectedLines * lineLength);
for (int i = 0; i < bytesLength; i += bytesPerLine)
{
line[0] = HexChars[(i >> 28) & 0xF];
line[1] = HexChars[(i >> 24) & 0xF];
line[2] = HexChars[(i >> 20) & 0xF];
line[3] = HexChars[(i >> 16) & 0xF];
line[4] = HexChars[(i >> 12) & 0xF];
line[5] = HexChars[(i >> 8) & 0xF];
line[6] = HexChars[(i >> 4) & 0xF];
line[7] = HexChars[(i >> 0) & 0xF];
int hexColumn = firstHexColumn;
int charColumn = firstCharColumn;
for (int j = 0; j < bytesPerLine; j++)
{
if (j > 0 && (j & 7) == 0) hexColumn++;
if (i + j >= bytesLength)
{
line[hexColumn] = ' ';
line[hexColumn + 1] = ' ';
line[charColumn] = ' ';
}
else
{
byte b = bytes[i + j];
line[hexColumn] = HexChars[(b >> 4) & 0xF];
line[hexColumn + 1] = HexChars[b & 0xF];
line[charColumn] = (b < 32 ? '·' : (char)b);
}
hexColumn += 3;
charColumn++;
}
result.Append(line);
}
return result.ToString();
}
}
}

Here's some simple code that will lump the bytes 4 at a time(step) with a space delimiter(delimiter):
int step = 4;
string delimiter = " ";
for(int i = 0; i < BytArr.Length;i += step)
{
for(int j = 0; j < step; j++)
{
Console.Write(BytArr[i + j].ToString("X2"));
}
Console.Write(delimiter);
}

URL shows how to dump in C. Search for C sample which is given towards the end of the page.
This URL shows example in C#

Convert a hex string (byte list) to a byte array

I want to convert a string ("00812B1FA4BEA310199D6E00DD010F5402000001807") to a byte array.
But I want each digit of the string to be the hex value.
Expected result:
array[0] = 0x00;
array[1] = 0x81;
array[0] = 0x2B;
array[0] = 0x1F;
etc...
I tried several methods. None gave the expected result. The closest ones were:
private static byte[] Convert(string tt)
{
byte[] bytes2 = new byte[tt.Length];
int i = 0;
foreach ( char c in tt)
{
bytes2[i++] = (byte)((int)c - 48);
}
return bytes2;
}
public static byte[] ConvertHexStringToByteArray(string hexString)
{
byte[] HexAsBytes = new byte[hexString.Length / 2];
for (int index = 0; index < HexAsBytes.Length; index++)
{
string byteValue = hexString.Substring(index * 2, 2);
byte[] a = GetBytes(byteValue);
HexAsBytes[index] = a[0];
}
return HexAsBytes;
}

Found solution here: How do you convert Byte Array to Hexadecimal String, and vice versa?
( answer starting by Inverse function for Waleed Eissa code)
Difficult to find because the thread has 36 answers.
public static byte[] HexToBytes(string hexString)
{
byte[] b = new byte[hexString.Length / 2];
char c;
for (int i = 0; i < hexString.Length / 2; i++)
{
c = hexString[i * 2];
b[i] = (byte)((c < 0x40 ? c - 0x30 : (c < 0x47 ? c - 0x37 : c - 0x57)) << 4);
c = hexString[i * 2 + 1];
b[i] += (byte)(c < 0x40 ? c - 0x30 : (c < 0x47 ? c - 0x37 : c - 0x57));
}
return b;
}

You can use Convert.ToByte to convert 2 hexadecimal chars to byte.
public static byte[] HexToByteArray(string hexstring)
{
var bytes = new List<byte>();
for (int i = 0; i < hexstring.Length/2; i++)
bytes.Add(Convert.ToByte("" + hexstring[i*2] + hexstring[i*2 + 1], 16));
return bytes.ToArray();
}

Send binary data as parameter to a method in Web Service?

In server side (C#.NET,Windows 2003) I have a web service with a method and in client side (Visual C++ v6, WinINet, POST) I want to call that method and pass binary data as a parameter to it.
when I send Binary data an error rise and when I send ASCII data it called successful.
How can I send binary data as parameter of a method?

To send binary data to a web method you can base64 encode it and then decode it in the web service. If your variable is a byte array called data then you would do the following.
In C++ you need to create a base64 header and cpp file. The following example is from http://www.adp-gmbh.ch/cpp/common/base64.html
base64.h
#include <string>
std::string base64_encode(unsigned char const* , unsigned int len);
std::string base64_decode(std::string const& s);
base64.cpp
#include "base64.h"
#include <iostream>
static const std::string base64_chars =
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz"
"0123456789+/";
static inline bool is_base64(unsigned char c) {
return (isalnum(c) || (c == '+') || (c == '/'));
}
std::string base64_encode(unsigned char const* bytes_to_encode, unsigned int in_len) {
std::string ret;
int i = 0;
int j = 0;
unsigned char char_array_3[3];
unsigned char char_array_4[4];
while (in_len--) {
char_array_3[i++] = *(bytes_to_encode++);
if (i == 3) {
char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
char_array_4[3] = char_array_3[2] & 0x3f;
for(i = 0; (i <4) ; i++)
ret += base64_chars[char_array_4[i]];
i = 0;
}
}
if (i)
{
for(j = i; j < 3; j++)
char_array_3[j] = '\0';
char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
char_array_4[3] = char_array_3[2] & 0x3f;
for (j = 0; (j < i + 1); j++)
ret += base64_chars[char_array_4[j]];
while((i++ < 3))
ret += '=';
}
return ret;
}
std::string base64_decode(std::string const& encoded_string) {
int in_len = encoded_string.size();
int i = 0;
int j = 0;
int in_ = 0;
unsigned char char_array_4[4], char_array_3[3];
std::string ret;
while (in_len-- && ( encoded_string[in_] != '=') && is_base64(encoded_string[in_])) {
char_array_4[i++] = encoded_string[in_]; in_++;
if (i ==4) {
for (i = 0; i <4; i++)
char_array_4[i] = base64_chars.find(char_array_4[i]);
char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
for (i = 0; (i < 3); i++)
ret += char_array_3[i];
i = 0;
}
}
if (i) {
for (j = i; j <4; j++)
char_array_4[j] = 0;
for (j = 0; j <4; j++)
char_array_4[j] = base64_chars.find(char_array_4[j]);
char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
for (j = 0; (j < i - 1); j++) ret += char_array_3[j];
}
return ret;
}
After you have your base64 implementation you can create the string to pass.
std::string encoded = base64_encode(data, sizeof(data));
You have to be mindful however of the fact that your data will expand by encoding it to Base64 so your uploads will take longer as the data will be larger. It will be approximately 37% larger (see the MIME section of http://en.wikipedia.org/wiki/Base64)
To decode the data on the other end you would simply do the following.
byte[] data = System.Convert.FromBase64String(yourParameterName);

How to convert a byte array to uint64 and back in C#?

I have been trying this for long. I have a byte array, which I want to convert to ulong and return the value to another function and that function should get the byte values back.
I tried bitshifting, but it was unsuccessfull in few cases. Is there any alternate to bitshifting? or do you have any short example? Thanks for the help.
Here is the bitshift code that I used, I don't understant why the second entry is not 00000001:
using System;
using System.Text;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
int[]responseBuffer = {0,1,2,3,4,5};
UInt64 my = (UInt64)(((UInt64)(((responseBuffer[0]) << 40) & 0xFF0000000000)) |
(UInt64)(((responseBuffer[1]) << 32) & 0x00FF00000000) |
(UInt64)(((responseBuffer[2]) << 24) & 0x0000FF000000) |
(UInt64)(((responseBuffer[3]) << 16) & 0x000000FF0000) |
(UInt64)(((responseBuffer[4]) << 8) & 0x00000000FF00) |
(UInt64)(responseBuffer[5] & 0xFF));
UInt64[] m_buffer = {(UInt64)((my >> 40) & 0xff),
(UInt64)((my >> 33) & 0xff) ,
(UInt64)((my >> 24) & 0xff) ,
(UInt64)((my>> 16) & 0xff) ,
(UInt64)((my>> 8) & 0xff) ,
(UInt64)(my& 0xff)};
Console.WriteLine("" + m_buffer[1]);
//string m_s = "";
StringBuilder sb = new StringBuilder();
for (int k = 0; k < 6; k++)
{
int value = (int)m_buffer[k];
for (int i = 7; i >= 0; i--)
{
if ((value >> i & 0x1) > 0)
{
sb.Append("1");
value &= (Byte)~(0x1 << i);
}
else
sb.Append("0");
}
sb.Append(" ");
}
Console.WriteLine(sb.ToString());
Console.Read();
}
}
}

Firstly I'd work out what went wrong with bitshifting, in case you ever needed it again. It should work fine.
Secondly, there's an alternative with BitConverter.ToUInt64 and BitConverter.GetBytes(ulong) if you're happy using the system endianness.
If you want to be able to specify the endianness, I have an EndianBitConverter class in my MiscUtil library which you could use.
(If you just need it to be reversible on the same sort of machine, I'd stick with the built in one though.)

I'm not sure what the point of the left bitshifting and right bitshifting you're doing initially.(i'm assuming you're trying to generate Uint64 values to test your function with).
To fix your function, just cast the numbers to UInt64 and then test them. Alternatively you can create long literals by using a suffix of l. such as UInt64[] responseBuffer = {0l,1l};
static void Main(string[] args)
{
int[] responseBuffer = { 0, 1, 2, 3, 4, 5 };
List<UInt64> bufferList = new List<ulong>();
foreach (var r in responseBuffer)
bufferList.Add((UInt64)r);
UInt64[] m_buffer = bufferList.ToArray();
foreach (var item in m_buffer)
Console.WriteLine(item);
//string m_s = "";
StringBuilder sb = new StringBuilder();
for (int k = 0; k < m_buffer.Length; k++)
{
int value = (int)m_buffer[k];
for (int i = 7; i >= 0; i--)
{
if ((value >> i & 0x1) > 0)
{
sb.Append("1");
value &= (Byte)~(0x1 << i);
}
else
sb.Append("0");
}
sb.Append(" ");
}
Console.WriteLine(sb.ToString());
}