Question

I have two questions.They both are concerning a void in C++,which I am trying to translate in C#.

C++ code

void Func_X_2(LPBYTE stream, DWORD key, BYTE keyByte) { stream[0] ^= (stream[0] + LOBYTE(LOWORD(key)) + keyByte); stream[1] ^= (stream[1] + HIBYTE(LOWORD(key)) + keyByte); stream[2] ^= (stream[2] + LOBYTE(HIWORD(key)) + keyByte); stream[3] ^= (stream[3] + HIBYTE(HIWORD(key)) + keyByte); stream[4] ^= (stream[4] + LOBYTE(LOWORD(key)) + keyByte); stream[5] ^= (stream[5] + HIBYTE(LOWORD(key)) + keyByte); stream[6] ^= (stream[6] + LOBYTE(HIWORD(key)) + keyByte); stream[7] ^= (stream[7] + HIBYTE(HIWORD(key)) + keyByte); } 

First question:

DWORD is UInt32,BYTE is byte,but what is LPBYTE? How to use it as an array?

Second question:

How to use LOBYTE,HIBYTE,LOWORD,HIWORD in C#?

EDIT

This is how the function is being called: C++ code

Func_X_2((LPBYTE)keyArray, dwArgs[14], keyByte); 

keyArray is a DWORD(UInt32),dwArgs is an array of dword.KeyByte is a byte.

Thanks in advance.

Answer 1

LPBYTE is a pointer to a byte array. The equivalent in C# would be a variable of type byte[]. So you could translate your function like so:

public static void Func_X_2(byte[] stream, int key, byte keyByte) {     stream[0] ^= (byte)(stream[0] + BitConverter.GetBytes(LoWord(key))[0]);     stream[1] ^= (byte)(stream[1] + BitConverter.GetBytes(LoWord(key))[1]);     stream[2] ^= (byte)(stream[2] + BitConverter.GetBytes(HiWord(key))[0]);     stream[3] ^= (byte)(stream[3] + BitConverter.GetBytes(HiWord(key))[1]);     stream[4] ^= (byte)(stream[4] + BitConverter.GetBytes(LoWord(key))[0]);     stream[5] ^= (byte)(stream[5] + BitConverter.GetBytes(LoWord(key))[1]);     stream[6] ^= (byte)(stream[6] + BitConverter.GetBytes(HiWord(key))[0]);     stream[7] ^= (byte)(stream[7] + BitConverter.GetBytes(HiWord(key))[1]); }  public static int LoWord(int dwValue) {     return (dwValue & 0xFFFF); }  public static int HiWord(int dwValue) {     return (dwValue >> 16) & 0xFFFF; }