Windows核心编程第二章,字符串的表示以及宽窄字符的转换

Char c = ‘A’
Char szBuff[] = “ABC”

Wchar_t  c = L’A’;  宽字符定义的时候需要加L表示这是个宽字符
Wchar_t  wzBuf[] = L”ABC”;定义字符串.

typedef wchar_t WCHAR;    // wc,   16-bit UNICODE character
#else
// some Macintosh compilers don't define wchar_t in a convenient location, or define it as a char
typedef unsigned short WCHAR;    // wc,   16-bit UNICODE character
#endif

typedef WCHAR *PWCHAR, *LPWCH, *PWCH;
typedef CONST WCHAR *LPCWCH, *PCWCH;

typedef _Null_terminated_ WCHAR *NWPSTR, *LPWSTR, *PWSTR;
typedef _Null_terminated_ PWSTR *PZPWSTR;
typedef _Null_terminated_ CONST PWSTR *PCZPWSTR;
typedef _Null_terminated_ WCHAR UNALIGNED *LPUWSTR, *PUWSTR;
typedef _Null_terminated_ CONST WCHAR *LPCWSTR, *PCWSTR;
typedef _Null_terminated_ PCWSTR *PZPCWSTR;
typedef _Null_terminated_ CONST PCWSTR *PCZPCWSTR;
typedef _Null_terminated_ CONST WCHAR UNALIGNED *LPCUWSTR, *PCUWSTR;

typedef _NullNull_terminated_ WCHAR *PZZWSTR;
typedef _NullNull_terminated_ CONST WCHAR *PCZZWSTR;
typedef _NullNull_terminated_ WCHAR UNALIGNED *PUZZWSTR;
typedef _NullNull_terminated_ CONST WCHAR UNALIGNED *PCUZZWSTR;

typedef  WCHAR *PNZWCH;
typedef  CONST WCHAR *PCNZWCH;
typedef  WCHAR UNALIGNED *PUNZWCH;
typedef  CONST WCHAR UNALIGNED *PCUNZWCH;

#if _WIN32_WINNT >= 0x0600 || (defined(__cplusplus) && defined(WINDOWS_ENABLE_CPLUSPLUS))

typedef CONST WCHAR *LPCWCHAR, *PCWCHAR;
typedef CONST WCHAR UNALIGNED *LPCUWCHAR, *PCUWCHAR;


_NullNull_terminated 宏的含义
宏是一个头部注解,藐视了一些类型.如何用作函数的参数以及返回值.
我们可以设置代码分析(Code Analysis) 把/analyze开关添加到编译器的命令行中.这样调用函数的话.编译器则会进行检测了.

#ifdef  UNICODE                     // 编译器使用ifdef语句自动判断你是否使用的是UNICODE字符集,如果是则下面生效.

#ifndef _TCHAR_DEFINED
typedef WCHAR TCHAR, *PTCHAR;
typedef WCHAR TBYTE , *PTBYTE ;
#define _TCHAR_DEFINED
#endif /* !_TCHAR_DEFINED */

typedef LPWCH LPTCH, PTCH;
typedef LPCWCH LPCTCH, PCTCH;
typedef LPWSTR PTSTR, LPTSTR;
typedef LPCWSTR PCTSTR, LPCTSTR;
typedef LPUWSTR PUTSTR, LPUTSTR;
typedef LPCUWSTR PCUTSTR, LPCUTSTR;
typedef LPWSTR LP;
typedef PZZWSTR PZZTSTR;
typedef PCZZWSTR PCZZTSTR;
typedef PUZZWSTR PUZZTSTR;
typedef PCUZZWSTR PCUZZTSTR;
typedef PZPWSTR PZPTSTR;
typedef PNZWCH PNZTCH;
typedef PCNZWCH PCNZTCH;
typedef PUNZWCH PUNZTCH;
typedef PCUNZWCH PCUNZTCH;
#define __TEXT(quote) L##quote      // r_winnt

#else   /* UNICODE */               // r_winnt

#ifndef _TCHAR_DEFINED
typedef char TCHAR, *PTCHAR;
typedef unsigned char TBYTE , *PTBYTE ;
#define _TCHAR_DEFINED
#endif /* !_TCHAR_DEFINED */

typedef LPCH LPTCH, PTCH;
typedef LPCCH LPCTCH, PCTCH;
typedef LPSTR PTSTR, LPTSTR, PUTSTR, LPUTSTR;
typedef LPCSTR PCTSTR, LPCTSTR, PCUTSTR, LPCUTSTR;
typedef PZZSTR PZZTSTR, PUZZTSTR;
typedef PCZZSTR PCZZTSTR, PCUZZTSTR;
typedef PZPSTR PZPTSTR;
typedef PNZCH PNZTCH, PUNZTCH;
typedef PCNZCH PCNZTCH, PCUNZTCH;
#define __TEXT(quote) quote         // r_winnt

#endif /* UNICODE */                // r_winnt
#define TEXT(quote) __TEXT(quote)   // r_winnt


typedef SHORT *PSHORT;  
typedef LONG *PLONG;    

#define _tcscat         wcscat
#define _tcscat_s       wcscat_s
#define _tcschr         wcschr
#define _tcscpy         wcscpy
#define _tcscpy_s       wcscpy_s
#define _tcscspn        wcscspn
#define _tcslen         wcslen
#define _tcsnlen        wcsnlen
#define _tcsncat        wcsncat
#define _tcsncat_s      wcsncat_s
#define _tcsncat_l      _wcsncat_l
#define _tcsncat_s_l    _wcsncat_s_l
#define _tcsncpy        wcsncpy
#define _tcsncpy_s      wcsncpy_s
#define _tcsncpy_l      _wcsncpy_l
#define _tcsncpy_s_l    _wcsncpy_s_l
#define _tcspbrk        wcspbrk
#define _tcsrchr        wcsrchr
#define _tcsspn         wcsspn
#define _tcsstr         wcsstr
#define _tcstok         _wcstok
#define _tcstok_s       wcstok_s
#define _tcstok_l       _wcstok_l
#define _tcstok_s_l     _wcstok_s_l
#define _tcserror       _wcserror
#define _tcserror_s     _wcserror_s
#define __tcserror      __wcserror
#define __tcserror_s    __wcserror_s

#define _tcsdup         _wcsdup
#define _tcsnset        _wcsnset
#define _tcsnset_s      _wcsnset_s
#define _tcsnset_l      _wcsnset_l
#define _tcsnset_s_l    _wcsnset_s_l
#define _tcsrev         _wcsrev
#define _tcsset         _wcsset
#define _tcsset_s       _wcsset_s
#define _tcsset_l       _wcsset_l
#define _tcsset_s_l     _wcsset_s_l

#define _tcscmp         wcscmp
#define _tcsicmp        _wcsicmp
#define _tcsicmp_l      _wcsicmp_l
#define _tcsnccmp       wcsncmp
#define _tcsncmp        wcsncmp
#define _tcsncicmp      _wcsnicmp
#define _tcsncicmp_l    _wcsnicmp_l
#define _tcsnicmp       _wcsnicmp
#define _tcsnicmp_l     _wcsnicmp_l

#define _tcscoll        wcscoll
#define _tcscoll_l      _wcscoll_l
#define _tcsicoll       _wcsicoll
#define _tcsicoll_l     _wcsicoll_l
#define _tcsnccoll      _wcsncoll
#define _tcsnccoll_l    _wcsncoll_l
#define _tcsncoll       _wcsncoll
#define _tcsncoll_l     _wcsncoll_l
#define _tcsncicoll     _wcsnicoll
#define _tcsncicoll_l   _wcsnicoll_l
#define _tcsnicoll      _wcsnicoll
#define _tcsnicoll_l    _wcsnicoll_l
使用  _t开头是Windows定义的宏,作用就是,当你定义了Unicode标准的时候,就会扩展为使用Unicode标注你的C库函数.如 _tcslen ,如果是Unicode标注,则使用 wcslen,否则则使用strlen.

    TCHAR Buffer[] = TEXT(“”);\
PTSTR Buffer = TEXT(‘a’);

Void *p = malloc(_countof(szbuffer));

int MultiByteToWideChar(UINT CodePage,
 DWORD dwFlags,
 _In_NLS_string_(cbMultiByte)LPCCHlpMultiByteStr, int cbMultiByte,
 LPWSTR lpWideCharStr,
 int cchWideChar );

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
int main()
{

    char szBuffer[] = "HelloWorld";
    DWORD szBufferLen = sizeof(szBuffer) / sizeof(szBuffer[0]);
    TCHAR wszBuffer[100] = { 0 };
    DWORD dwWszBufferLen = 100;

    MultiByteToWideChar(CP_ACP, 0, szBuffer, szBufferLen,(LPWSTR)&wszBuffer, dwWszBufferLen);

    printf("%ls \r\n", wszBuffer);
    system("pause");

    return 0;
}

int
WINAPI
WideCharToMultiByte(
    _In_ UINT CodePage,
    _In_ DWORD dwFlags,
    _In_NLS_string_(cchWideChar) LPCWCH lpWideCharStr,
    _In_ int cchWideChar,
    _Out_writes_bytes_to_opt_(cbMultiByte,return) LPSTR lpMultiByteStr,
    _In_ int cbMultiByte,
    _In_opt_ LPCCH lpDefaultChar,
    _Out_opt_ LPBOOL lpUsedDefaultChar
    );

int main()
{

    TCHAR wzBuffer[] = TEXT("HelloWorld");
    char szBuff[100] = { 0 };
    DWORD szBufflen = 100;
    DWORD dwWzBufferlen = (sizeof(wzBuffer) / sizeof(wzBuffer[0])) * 2;

    WideCharToMultiByte(CP_ACP, 0,wzBuffer, dwWzBufferlen, szBuff, szBufflen, 0, 0);
    

    printf("%s \r\n", szBuff);
    system("pause");

    return 0;
}