Re: Converting BSTR to char*

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Aidal wrote:

Hi NG.

First of, I'm new to VC++ and C++ in general, so don't bite my head of for asking noob questions please :)

I'm trying to build a rather simple DLL and I need to convert a BSTR to char*.


First, you should realize that a BSTR is a (special kind of) wide character string (16-bit), whereas char* is a narrow (8-bit) string.

Second, you may not really be wanting a char*. If you are in a Unicode build (a wise choice, usually) then you probably want a wchar_t*. Learn to use TCHAR, LPTSTR, etc, which are narrow in ANSI builds and wide in UNICODE builds.

Third, you probably really want a const char* (or const wchar_t*).

Fourth, use of BSTR is much easier if you use the _bstr_t wrapper. This actually maintains both a narrow and wide string internally, and has cast operators for both const char* and const wchar_t*.

C++ string handling in Windows is not easy. Good luck!

David Wilkinson
.

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