Method ExecuteToJsonMethod

cpp/iedriver/VariantUtilities.cpp:318–385

}

bool VariantUtilities::ExecuteToJsonMethod(VARIANT object_to_serialize,
                                           VARIANT* json_object_variant) {
  CComVariant to_json_method;
  bool has_to_json_property = GetVariantObjectPropertyValue(object_to_serialize.pdispVal,
                                                            L"toJSON",
                                                            &to_json_method);
  if (!has_to_json_property) {
    LOG(DEBUG) << "No toJSON property found on IDispatch";
    return false;
  }

  // Grab the "call" method out of the returned function
  DISPID call_member_id;
  OLECHAR FAR* call_member_name = L"call";
  HRESULT hr = to_json_method.pdispVal->GetIDsOfNames(IID_NULL,
                                                      &call_member_name,
                                                      1,
                                                      LOCALE_USER_DEFAULT,
                                                      &call_member_id);
  if (FAILED(hr)) {
    LOGHR(WARN, hr) << "Cannot locate call method on toJSON function";
    return false;
  }

  // IDispatch::Invoke() expects the arguments to be passed into it
  // in reverse order. To accomplish this, we create a new variant
  // array of size n + 1 where n is the number of arguments we have.
  // we copy each element of arguments_array_ into the new array in
  // reverse order, and add an extra argument, the window object,
  // to the end of the array to use as the "this" parameter for the
  // function invocation.
  std::vector<CComVariant> argument_array(1);
  argument_array[0].Copy(&object_to_serialize);

  DISPPARAMS call_parameters = { 0 };
  memset(&call_parameters, 0, sizeof call_parameters);
  call_parameters.cArgs = static_cast<unsigned int>(argument_array.size());
  call_parameters.rgvarg = &argument_array[0];

  CComBSTR error_description = L"";

  int return_code = WD_SUCCESS;
  EXCEPINFO exception;
  memset(&exception, 0, sizeof exception);
  hr = to_json_method.pdispVal->Invoke(call_member_id,
                                       IID_NULL,
                                       LOCALE_USER_DEFAULT,
                                       DISPATCH_METHOD,
                                       &call_parameters,
                                       json_object_variant,
                                       &exception,
                                       0);

  if (FAILED(hr)) {
    if (DISP_E_EXCEPTION == hr) {
      error_description = exception.bstrDescription ? exception.bstrDescription : L"EUNEXPECTEDJSERROR";
      CComBSTR error_source(exception.bstrSource ? exception.bstrSource : L"EUNEXPECTEDJSERROR");
      LOG(INFO) << "Exception message was: '" << error_description << "'";