int main()
{
// Initialize COM.
HRESULT hr = CoInitialize(nullptr);
// Create the interface pointer.
ICalculator *calculator = nullptr;
hr = CoCreateInstance(__uuidof(Calculator), nullptr, CLSCTX_INPROC_SERVER, __uuidof(ICalculator), (void**)&calculator);
long result = 0;
// Addition
calculator->Add(1, 1, &result);
std::cout << "1 + 1 = " << result << std::endl;
// Subtraction
calculator->Subtract(10, 5, &result);
std::cout << "10 - 5 = " << result << std::endl;
// Multiplication
calculator->Multiply(10, 10, &result);
std::cout << "10 * 10 = " << result << std::endl;
// Division
calculator->Divide(10, 5, &result);
std::cout << "10 / 5 = " << result << std::endl;
// Passing string to COM C# library
// This is more appropriate:
// BSTR number = _bstr_t("100");
// calculator->ToNumber(number, &result);
// This is shorter
calculator->ToNumber(_bstr_t("100"), &result);
std::cout << "Convert string \"100\" to number: " << result << std::endl;
system("pause");
CoUninitialize();
return 0;
}
