#include <iostream><br/>#include <windows.h><br/>#include <shlwapi.h><br/>#pragma comment(lib,"shlwapi.lib")<br/>using namespace std;

inline BYTE CharToBin(TCHAR ch)
{
if(ch>='0' && ch<='9')
return ch - '0';
if(ch>='a' && ch<='f')
return ch - 'a' + 10;
if(ch>='A' && ch<= 'F')
return ch - 'A' + 10;
return 0xff;
}

inline bool Hex2Bin(LPCTSTR lpHex,LPBYTE lpBin,DWORD &dwLen)
{
LPCTSTR lpChar = lpHex;
TCHAR char1 = *lpChar;
TCHAR char2 = *(lpChar+1);
if(!char1 || !char2)
return false;

LPBYTE lpOut = lpBin;

DWORD inputBuf = dwLen;
dwLen = 0;

BYTE h = CharToBin(char1);
BYTE l = CharToBin(char2);
while(0xff != h && 0xff != l)
{
*lpOut = l | h<<4;
lpOut++;

dwLen++;

lpChar+=2;
if(inputBuf<=dwLen)
break;

h = CharToBin(*lpChar);
l = CharToBin(*(lpChar+1));
}
return true;
}

BOOL RegWrite(HKEY hKey,LPCSTR lpSubKey,LPCSTR lpValue,DWORD dwType,void* pData,DWORD dwLen)
{
if(!pData)
return FALSE;

if(REG_BINARY == dwType)
{
void* pBuffer = new BYTE[lstrlen((char*)pData)];
memset(pBuffer,0,lstrlen((char*)pData));
if(pBuffer)
{
Hex2Bin((LPCTSTR)pData,(LPBYTE)pBuffer,dwLen);
SHSetValue(hKey,lpSubKey,lpValue,REG_BINARY,pBuffer,dwLen);
delete []pBuffer;
}
}
else
{
if(REG_SZ == dwType)
{
dwLen = lstrlen((const char*)pData);
}
else if(REG_DWORD == dwType)
dwLen = 4;
SHSetValue(hKey,lpSubKey,lpValue,dwType,pData,dwLen);
}

return TRUE;
}

void main(int argc,char*argv[])
{
  RegWrite(HKEY_LOCAL_MACHINE,"SOFTWARE//aaaa//","b",REG_BINARY,"123456abcdef",6);

DWORD dwValue = 1234;
  RegWrite(HKEY_LOCAL_MACHINE,"SOFTWARE//aaaa//","c",REG_DWORD,&dwValue,4);

RegWrite(HKEY_LOCAL_MACHINE,"SOFTWARE//aaaa//","d",REG_SZ,"asdfgh",0);
}