windows 将 BSTR 转换为 wstring
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convert BSTR to wstring
提问by karikari
How to convert a char[256] to wstring?
如何将 char[256] 转换为 wstring？
update. here is my current code:
更新。这是我当前的代码：
char testDest[256];
char *p= _com_util::ConvertBSTRToString(url->bstrVal);
for (int i = 0; i <= strlen(p); i++)
{
testDest[i] = p[i];
}
// need to convert testDest to wstring to I can pass it to this below function...
writeToFile(testDestwstring);
回答by Steve Townsend
If your input is BSTR(as it seems to be) the data is already Unicode and you can just cast this directly to wstringas follows. _bstr_thas implicit conversions to both char*and wchar*which avoid the need for manual Win32 code conversion.
如果您的输入是BSTR（看起来是）数据已经是 Unicode，您可以直接将其转换wstring为如下所示。 _bstr_t具有对两者的隐式转换char*，wchar*从而避免了手动 Win32 代码转换的需要。
if (url->bstrVal)
{
// true => make a new copy - can avoid this if source
// no longer needed, by using false here and avoiding SysFreeString on source
const _bstr_t wrapper(url->bstrVal, true);
std::wstring wstrVal((const _wchar_t*)wrapper);
}
See herefor more details on this area of Windows usage. It's easy to mess up the use of the Win32 API in this area - using the BSTR wrapper to do this avoids both data copy (if used judiciously) and code complexity.
有关Windows 使用方面的更多详细信息，请参见此处。在这方面很容易弄乱 Win32 API 的使用 - 使用 BSTR 包装器来做到这一点可以避免数据复制（如果使用得当）和代码复杂性。
回答by renick
MultiByteToWideCharwill return a UTF-16 string. You need to specify the source codepage.
MultiByteToWideChar将返回一个 UTF-16 字符串。您需要指定源代码页。
