I'm not very familiar with managed C++. I think you can first convert the
System::String to an  wide char,an then convert this wide char to BSTR.
From MSDN you can get the first step as follows:

// convert_string_to_wchar.cpp
// compile with: /clr
#include < stdio.h >
#include < stdlib.h >
#include < vcclr.h >

using namespace System;

int main() {
  String ^str = "Hello";

  // Pin memory so GC can't move it while native function is called
  pin_ptr<const wchar_t> wch = PtrToStringChars(str);
  printf_s("%S\n", wch);

  // Conversion to char* :
  // Can just convert wchar_t* to char* using one of the
  // conversion functions such as:
  // WideCharToMultiByte()
  // wcstombs_s()
  // ... etc
  size_t convertedChars = 0;
  size_t  sizeInBytes = ((str->Length + 1) * 2);
  errno_t err = 0;
  char    *ch = (char *)malloc(sizeInBytes);

  err = wcstombs_s(&convertedChars,
                   ch, sizeInBytes,
                   wch, sizeInBytes);
  if (err != 0)
     printf_s("wcstombs_s  failed!\n");

   printf_s("%s\n", ch);
}And in second step using ::SysAllocString to conver the wchar to BSTR or
using _bstr_t.

"lencastro" <lencastro@gmail.com>
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