简单有关问题,数据类型转换的有关问题.非常感谢

#include "stdafx.h"

#include <Windows.h>

int _tmain(int argc, _TCHAR* argv[])
{
    SYSTEMTIME systime;
    GetLocalTime(&systime);
    TCHAR szBuf[10] = {0};
    _stprintf_s(szBuf, _countof(szBuf), _T("%04d%02d%02d"), systime.wYear, systime.wMonth, systime.wDay);
    int len = _tcslen(szBuf);
    BYTE* pData = new BYTE[len];
    memset(pData, 0, len * sizeof(BYTE));
    for(int i=0; i<len; i++)
    {
        pData[i] = szBuf[i] - 0x30;
    }

    TCHAR buf[256] = {0};
    TCHAR tmp[10] = {0};
    for(int i=0; i<len; i++)
    {
        _stprintf_s(tmp, _countof(tmp), _T("0x%02x, "), pData[i]);
        _tcscat_s(buf, _countof(buf) - _tcslen(buf), tmp);
    }
    _tprintf(_T("%s\n"), buf);
    return 0;
}