Windows下提供了两个编码转换函数：WideCharToMultiByte和MultiByteToWideChar。

用它们可实现Unicode(UCS2)，UTF8，GBK(GB2312)互转。这两个函数的原型是：

int

WINAPI

MultiByteToWideChar(

__in UINT CodePage,

__in DWORD dwFlags,

__in_bcount(cbMultiByte) LPCSTR lpMultiByteStr,

__in int cbMultiByte,

__out_ecount_opt(cchWideChar) __transfer(lpMultiByteStr) LPWSTR lpWideCharStr,

__in int cchWideChar);

int

WINAPI

WideCharToMultiByte(

__in UINT CodePage,

__in DWORD dwFlags,

__in_ecount(cchWideChar) LPCWSTR lpWideCharStr,

__in int cchWideChar,

__out_bcount_opt(cbMultiByte) __transfer(lpWideCharStr) LPSTR lpMultiByteStr,

__in int cbMultiByte,

__in_opt LPCSTR lpDefaultChar,

__out_opt LPBOOL lpUsedDefaultChar);