在 C++ 中将 std::wstring 转换为 const *char
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convert std::wstring to const *char in c++
提问by subs
How can I convert std::wstringto const *charin C++?
如何在 C++ 中转换std::wstring为const *char？
采纳答案by icecrime
You can convert a std::wstringto a const wchar_t *using the c_strmember function :
您可以使用成员函数将 a 转换std::wstring为 a ：const wchar_t *c_str
std::wstring wStr;
const wchar_t *str = wStr.c_str();
However, a conversion to a const char *isn't natural : it requires an additional call to std::wcstombs, like for example:
但是，转换为 aconst char *并不自然：它需要额外调用std::wcstombs，例如：
#include <cstdlib>
// ...
std::wstring wStr;
const wchar_t *input = wStr.c_str();
// Count required buffer size (plus one for null-terminator).
size_t size = (wcslen(input) + 1) * sizeof(wchar_t);
char *buffer = new char[size];
#ifdef __STDC_LIB_EXT1__
// wcstombs_s is only guaranteed to be available if __STDC_LIB_EXT1__ is defined
size_t convertedSize;
std::wcstombs_s(&convertedSize, buffer, size, input, size);
#else
std::wcstombs(buffer, input, size);
#endif
/* Use the string stored in "buffer" variable */
// Free allocated memory:
delete buffer;
回答by Jon
You cannot do this just like that. std::wstringrepresents a string of wide (Unicode) characters, while char*in this case is a string of ASCII characters. There has to be a code page conversion from Unicode to ASCII.
你不能就那样做。std::wstring表示一串宽 (Unicode) 字符，而char*在本例中是一串 ASCII 字符。必须有一个从 Unicode 到 ASCII 的代码页转换。
To make the conversion you can use standard library functions such as wcstombs, or Windows' WideCharToMultiBytefunction.
要进行转换，您可以使用标准库函数，例如wcstombs、 或 Windows 的WideCharToMultiByte函数。
Updatedto incorporate information from comments, thanks for pointing that out.
更新以合并评论中的信息，感谢您指出这一点。
