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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#

Pack and unpack multiple integers into and from an Uint64

Need to pack and unpack the following into an UInt64
UInt25
UInt5
UInt7
UInt27
Have the following for packing and unpacking UInt27 and UInt5 to from UInt32
But I cannot get past 2
My background is math (not computer science)
UInt32 highlow;
UInt32 high;
byte low;
int two27 = (Int32)Math.Pow(2, 27);
for (UInt32 i = 0; i < two27; i++)
{
highlow = ((UInt32)i) << 5;
high = highlow >> 5;
if (high != i)
{
Debug.WriteLine("high wrong A " + high.ToString() + " " + i.ToString());
}
for (byte j = 0; j < 32; j++)
{
highlow = (((UInt32)i) << 5) | j;
high = highlow >> 5;
if (high != i)
{
Debug.WriteLine("high wrong B " + high.ToString() + " " + i.ToString());
}
low = (byte)(highlow & 0x1f);
if (low != j)
{
Debug.WriteLine("low wrong " + low.ToString() + " " + j.ToString());
}
}
}
Code based on accepted answer (did not test the full loop the i27 loop got to 2)
UInt32 bits27;
UInt32 bits25;
UInt32 bits7;
UInt32 bits5;
UInt32 int27 = (UInt32)Math.Pow(2,27);
UInt32 int25 = (UInt32)Math.Pow(2,25);
UInt32 int7 = (UInt32)Math.Pow(2,7);
UInt32 int5 = (UInt32)Math.Pow(2,5);
UInt64 packed;
//ulong packed = (bits27) | ((ulong)bits25 << 27) | ((ulong)bits7 << 52) | ((ulong)bits5 << 59);
for (UInt32 i27 = 0; i27 < int27; i27++)
{
for (UInt32 i25 = 0; i25 < int25; i25++)
{
for (UInt32 i7 = 0; i7 < int7; i7++)
{
for (UInt32 i5 = 0; i5 < int5; i5++)
{
packed = (UInt64)(i27) | ((UInt64)i25 << 27) | ((UInt64)i7 << 52) | ((UInt64)i5 << 59);
bits27 = (UInt32)(packed & ((1 << 27) - 1));
bits25 = (UInt32)((packed >> 27) & ((1 << 25) - 1));
bits7 = (UInt32)((packed >> 52) & ((1 << 7) - 1));
bits5 = (UInt32)((packed >> 59) & ((1 << 5) - 1));
if (bits27 != i27) Debug.WriteLine("bits27 != i27");
if (bits25 != i25) Debug.WriteLine("bits25 != i25");
if (bits7 != i7) Debug.WriteLine("bits7 != i7");
if (bits5 != i5) Debug.WriteLine("bits5 != i5");
}
}
}
}

The shift operators are the right solution, but note that they won't automatically make the result wider than the inputs -- you need to cast the input.
Pack:
ulong packed = (bits27) | ((ulong)bits25 << 27) | ((ulong)bits7 << 52) | ((ulong)bits5 << 59);
Unpack:
bits27 = (uint) (packed & ((1 << 27) - 1));
bits25 = (uint)((packed >> 27) & ((1 << 25) - 1));
bits7 = (uint)((packed >> 52) & ((1 << 7) - 1));
bits5 = (uint)((packed >> 59) & ((1 << 5) - 1));

It seems like it would be far easier to convert the numbers to binary, pad or truncate to the correct length, concatenate them and then construct your 64-bit type from binary.
var packedInt64 = Convert.ToInt64(Convert.ToString(ui25, 2).PadLeft(25, '0') +
Convert.ToString(ui5, 2).PadLeft(5, '0') +
Convert.ToString(ui7, 2).PadLeft(7, '0') +
Convert.ToString(ui27, 2).PadLeft(2, '0'), 2);
To unpack:
var binary = Convert.ToString(packedInt64, 2);
ui25 = Convert.ToUInt32(binary.Substring(0, 24));
ui5 = Convert.ToUInt32(binary.Substring(24, 5));
etc.

hakmem algorithm

I see this hakmem algorithm:
int pop(unsigned x) {
unsigned n;
n = (x >> 1) & 0x77777777;
x = x - n;
n = (n >> 1) & 0x77777777;
x = x - n;
n = (n >> 1) & 0x77777777;
x = x - n;
x = (x + (x >> 4)) & 0x0F0F0F0F;
x = x * 0x01010101;
return x >> 24;
}
Is possible change it for a long of 64 bits?

You are calculating what is known as the "Hamming weight", which for integers means the number of binary "1" bits in the number. For binary numbers, this is also known as the "population count".
There are several ways to implement this for 64 bits.
Please see the Wiki page for details.
Here's an implementation stolen from here:
public int Pop(ulong w)
{
w -= (w >> 1) & 0x5555555555555555UL;
w = (w & 0x3333333333333333UL) + ((w >> 2) & 0x3333333333333333UL);
w = (w + (w >> 4)) & 0x0f0f0f0f0f0f0f0fUL;
return (int)((w * 0x0101010101010101UL) >> 56);
}

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());
}

ushort array to byte array

I have an array of ushorts, with each ushort representing a 12-bit word. This needs to be tightly packed into an array of bytes. It should look like this in the end:
| word1 | word2 | word3 | word4 |
| byte1 | byte2 | byte3 | byte4 | byte5 | byte6|
Since each word only uses 12 bits, 2 words will be packed into 3 bytes.
Could someone help? I'm a bit stuck on how to do this in C#.

You're probably going to have to brute-force it.
I'm not a C# guy, but you are looking at something along the lines of (in C):
unsigned incursor, outcursor;
unsigned inlen = length(inputarray); // not literally
for(incursor=0,outcursor=0;incursor < inlen; incursor+=2,outcursor+=3{
outputarray[outcursor+0] = ((inputarray[incursor+0]) >> 4) & 0xFF;
outputarray[outcursor+1] = ((inputarray[incursor+0] & 0x0F)<<4 | ((inputarray[incursor+1]>>8) & 0x0F);
outputarray[outcursor+2] = inputarray[incursor+1] & 0xFF;
}

If you want to use the array as an array of UInt16 while in-memory, and then convert it to a packed byte array for storage, then you'll want a function to do one-shot conversion of the two array types.
public byte[] PackUInt12(ushort[] input)
{
byte[] result = new byte[(input.Length * 3 + 1) / 2]; // the +1 leaves space if we have an odd number of UInt12s. It's the unused half byte at the end of the array.
for(int i = 0; i < input.Length / 2; i++)
{
result[i * 3 + 0] = (byte)input[i * 2 + 0];
result[i * 3 + 1] = (byte)(input[i * 2 + 0] >> 8 | input[i * 2 + 1] << 4);
result[i * 3 + 2] = (byte)(input[i * 2 + 1] >> 4);
}
if(input.Length % 2 == 1)
{
result[i * 3 + 0] = (byte)input[i * 2 + 0];
result[i * 3 + 1] = (byte)(input[i * 2 + 0] >> 8);
}
return result;
}
public ushort[] UnpackUInt12(byte[] input)
{
ushort[] result = new ushort[input.Length * 2 / 3];
for(int i = 0; i < input.Length / 3; i++)
{
result[i * 2 + 0] = (ushort)(((ushort)input[i * 3 + 1]) << 8 & 0x0F00 | input[i * 3 + 0]);
result[i * 2 + 1] = (ushort)(((ushort)input[i * 3 + 1]) << 4 | input[i * 3 + 1] >> 4;)
}
if(result.Length % 2 == 1)
{
result[i * 2 + 0] = (ushort)(((ushort)input[i * 3 + 1]) << 8 & 0x0F00 | input[i * 3 + 0]);
}
return result;
}
If, however, you want to be efficient about memory usage while the application is running, and access this packed array as an array, then you'll want to have a class that returns ushorts, but stores them in byte[].
public class UInt12Array
{
// TODO: Constructors, etc.
private byte[] storage;
public ushort this[int index]
{
get
{
// TODO: throw exceptions if the index is off the array.
int i = index * 2 / 3;
if(index % 2 == 0)
return (ushort)(((ushort)storage[i * 3 + 1]) << 8 & 0x0F00 | storage[i * 3 + 0]);
else
return (ushort)(((ushort)storage[i * 3 + 1]) << 4 | storage[i * 3 + 1] >> 4;)
}
set
{
// TODO: throw exceptions if the index is off the array.
int i = index * 2 / 3;
if(index % 2 == 0)
storage[i * 3 + 0] = (byte)value;
storage[i * 3 + 1] = (byte)(value >> 8 | storage[i * 3 + 1] & 0xF0);
else
storage[i * 3 + 1] = (byte)(storage[i * 3 + 1] & 0x0F | value << 4);
storage[i * 3 + 2] = (byte)(value >> 4);
}
}
}

Why not store the 12-bit words in a byte array and provide a getter and a setter method that read and write the ushort's byte to the correct index in the array?

Trying to solve this with LINQ was fun!
Warning: For entertainment purposes only - do not use the below performance abominations in real code!
First try - group pairs of uints, create three bytes out of each pair, flatten list:
byte[] packedNumbers = (from i in Enumerable.Range(0, unpackedNumbers.Length)
group unpackedNumbers[i] by i - (i % 2) into pairs
let n1 = pairs.First()
let n2 = pairs.Skip(1).First()
let b1 = (byte)(n1 >> 4)
let b2 = (byte)(((n1 & 0xF) << 4) | (n2 & 0xF00) >> 8)
let b3 = (byte)(n2 & 0xFFFF)
select new[] { b1, b2, b3 })
.SelectMany(b => b).ToArray();
Or slightly more compact, but less readable:
byte[] packedNumbers = unpackedNumbers
.Select((Value, Index) => new { Value, Index })
.GroupBy(number => number.Index - (number.Index % 2))
.SelectMany(pair => new byte[] {
(byte)(pair.First().Value >> 4),
(byte)(((pair.First().Value & 0xF) << 4) | (pair.Skip(1).First().Value & 0xF00) >> 8),
(byte)(pair.Skip(1).First().Value & 0xFFFF) }).ToArray();
Strings anyone?
char[] hexChars = unpackedNumbers.SelectMany(n => n.ToString("X4").Substring(1, 3)).ToArray();
byte[] packedNumbers = (from i in Enumerable.Range(0, hexChars.Length / 2)
select byte.Parse(hexChars[i * 2].ToString() + hexChars[i * 2 + 1], NumberStyles.HexNumber))
.ToArray();

According to the comments given, I suppose, the current answers is preferable.
But about this should do it also:
public byte[] ushort2byteArr(ushort[] arr) {
System.IO.MemoryStream ms = new System.IO.MemoryStream();
System.IO.BinaryWriter bw = new System.IO.BinaryWriter(ms);
for (int i = 0; i < arr.Length-1;) { // check upper limit!
// following is wrong! must extend this to pack 8 12 bit words into 3 uint32!
UInt32 tmp = arr[i++] | (arr[i++] << 12) ... ;
bw.Write(tmp);
}
return ms.ToArray();
}
its not tested. take it as pseudocode to get the clue. especially the word -> uint32 conversion. May need some padding at the end?
#edit: made a function out of it for better clearance