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[ at ]gmail.com>
??????:1169297004.487965.162140[ at ]11g2000cwr.googlegroups.com...
[Quoted Text] >i am creating a addin for outlook express in vc++2005
>
> I am trying to load xml to my code with the following code
>
> STDMETHOD(GetCustomUI)(BSTR RibbonID, BSTR * RibbonXml)
> {
> Assembly^ assem=Assembly::GetExecutingAssembly();
> Stream^ strm=
> assem->GetManifestResourceStream("test.Xmlres.test.xml");
> StreamReader^ reader= gcnew StreamReader(strm);
> *RibbonXml= reader->ReadToEnd();
> reader->Close();
> strm->Close();
> return S_OK;
>
> }
>
>
> but it showing an error in compile time:
>
> error C2440: '=' : cannot convert from 'System::String ^' to 'BSTR'
> No user-defined-conversion operator available, or
> Cannot convert a managed type to an unmanaged type
>
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