C++ HandleScope函数代码示例

void CJSKadID::FxToString(const v8::FunctionCallbackInfo<v8::Value> &args)
{
	v8::HandleScope HandleScope(v8::Isolate::GetCurrent());
	CJSKadID* jKadID = GetJSObject<CJSKadID>(args.Holder());

	args.GetReturnValue().Set(v8::String::NewFromTwoByte(v8::Isolate::GetCurrent(), V8STR(jKadID->m_pKadID->m_Value.ToHex().c_str())));
}

/** toString:
* convert the buffer into a hex encoded string
* 
* @return string
*	Hex Encoded buffer content
*/
void CJSBuffer::FxToString(const v8::FunctionCallbackInfo<v8::Value> &args)
{
	v8::HandleScope HandleScope(v8::Isolate::GetCurrent());
	CBufferObj* pBuffer = GetCObject<CBufferObj>(args.Holder());

	args.GetReturnValue().Set(v8::String::NewFromTwoByte(v8::Isolate::GetCurrent(), V8STR(ToHex(pBuffer->GetBuffer(), pBuffer->GetSize()).c_str())));
}

PJsonVal TNodeJsStreamAggr::SaveJson(const int& Limit) const {
	if (!SaveJsonFun.IsEmpty()) {
		v8::Isolate* Isolate = v8::Isolate::GetCurrent();
		v8::HandleScope HandleScope(Isolate);

		v8::Local<v8::Function> Callback = v8::Local<v8::Function>::New(Isolate, SaveJsonFun);
		v8::Local<v8::Object> GlobalContext = Isolate->GetCurrentContext()->Global();
		const unsigned Argc = 1;
		v8::Local<v8::Value> ArgV[Argc] = { v8::Number::New(Isolate, Limit) };
		v8::TryCatch TryCatch;
		v8::Local<v8::Value> ReturnVal = Callback->Call(GlobalContext, Argc, ArgV);
		if (TryCatch.HasCaught()) {
			TryCatch.ReThrow();	
			return TJsonVal::NewObj();
		}
		QmAssertR(ReturnVal->IsObject(), "Stream aggr JS callback: saveJson didn't return an object.");
		PJsonVal Res = TNodeJsUtil::GetObjJson(ReturnVal->ToObject());

		QmAssertR(Res->IsDef(), "Stream aggr JS callback: saveJson didn't return a valid JSON.");
		return Res;
	}
	else {
		return TJsonVal::NewObj();
	}
}

void TNodeJsFIn::Init(v8::Handle<v8::Object> exports) {
	v8::Isolate* Isolate = v8::Isolate::GetCurrent();
	v8::HandleScope HandleScope(Isolate);
	// template for creating function from javascript using "new", uses _NewJs callback
	v8::Local<v8::FunctionTemplate> tpl = v8::FunctionTemplate::New(Isolate, TNodeJsUtil::_NewJs<TNodeJsFIn>);
	// child will have the same properties and methods, but a different callback: _NewCpp
	v8::Local<v8::FunctionTemplate> child = v8::FunctionTemplate::New(Isolate, TNodeJsUtil::_NewCpp<TNodeJsFIn>);
	child->Inherit(tpl);

	child->SetClassName(v8::String::NewFromUtf8(Isolate, GetClassId().CStr()));
	// ObjectWrap uses the first internal field to store the wrapped pointer
	child->InstanceTemplate()->SetInternalFieldCount(1);
	
	tpl->SetClassName(v8::String::NewFromUtf8(Isolate, GetClassId().CStr()));
	// ObjectWrap uses the first internal field to store the wrapped pointer
	tpl->InstanceTemplate()->SetInternalFieldCount(1);

	// Add all prototype methods, getters and setters here
	NODE_SET_PROTOTYPE_METHOD(tpl, "peekCh", _peekCh);
	NODE_SET_PROTOTYPE_METHOD(tpl, "getCh", _getCh);
    NODE_SET_PROTOTYPE_METHOD(tpl, "readLine", _readLine);
    NODE_SET_PROTOTYPE_METHOD(tpl, "readJson", _readJson);
	NODE_SET_PROTOTYPE_METHOD(tpl, "readAll", _readAll);
	// Add properties
	tpl->InstanceTemplate()->SetAccessor(v8::String::NewFromUtf8(Isolate, "eof"), _eof);
	tpl->InstanceTemplate()->SetAccessor(v8::String::NewFromUtf8(Isolate, "length"), _length);

	// This has to be last, otherwise the properties won't show up on the object in JavaScript	
	// Constructor is used when creating the object from C++
	Constructor.Reset(Isolate, child->GetFunction());
	// we need to export the class for calling using "new FIn(...)"
	exports->Set(v8::String::NewFromUtf8(Isolate, GetClassId().CStr()),
		tpl->GetFunction());
}

void TNodeJsFIn::New(const v8::FunctionCallbackInfo<v8::Value>& Args) {
    v8::Isolate* Isolate = v8::Isolate::GetCurrent();
    v8::HandleScope HandleScope(Isolate);

    if (Args.IsConstructCall()) {
        EAssertR(Args.Length() == 1 && Args[0]->IsString(),
            "Expected a file path.");
        TStr FNm(*v8::String::Utf8Value(Args[0]->ToString()));
        EAssertR(TFile::Exists(FNm), "File does not exist.");

        TNodeJsFIn* JsFIn = new TNodeJsFIn(FNm);
        v8::Local<v8::Object> Instance = Args.This();
		
		v8::Handle<v8::String> key = v8::String::NewFromUtf8(Isolate, "class");
		v8::Handle<v8::String> value = v8::String::NewFromUtf8(Isolate, ClassId.CStr());
		Instance->SetHiddenValue(key, value);

        JsFIn->Wrap(Instance);
        Args.GetReturnValue().Set(Instance);
    } else {
        const int Argc = 1;
        v8::Local<v8::Value> Argv[Argc] = { Args[0] };
        v8::Local<v8::Function> cons = v8::Local<v8::Function>::New(Isolate, constructor);
        v8::Local<v8::Object> Instance = cons->NewInstance(Argc, Argv);
        Args.GetReturnValue().Set(Instance);
    }
}

TNodeJsRf24Radio* TNodeJsRf24Radio::NewFromArgs(const v8::FunctionCallbackInfo<v8::Value>& Args) {
	v8::Isolate* Isolate = v8::Isolate::GetCurrent();
	v8::HandleScope HandleScope(Isolate);

	PJsonVal ParamJson = TNodeJsUtil::GetArgJson(Args, 0);

	const int PinCE = ParamJson->GetObjInt("pinCE");
	const int PinCSN = ParamJson->GetObjInt("pinCSN");
	const uint16 MyId = (uint16) ParamJson->GetObjInt("id");
	const PJsonVal SensorJsonV = ParamJson->GetObjKey("sensors");

	const bool Verbose = ParamJson->GetObjBool("verbose", false);
	const PNotify Notify = Verbose ? TNotify::StdNotify : TNotify::NullNotify;

	Notify->OnNotify(TNotifyType::ntInfo, "Parsing configuration ...");

	TStrIntH SensorNmIdH;
	TStrIntH SensorIdNodeIdH;

	for (int SensorN = 0; SensorN < SensorJsonV->GetArrVals(); SensorN++) {
		const PJsonVal SensorJson = SensorJsonV->GetArrVal(SensorN);
		const TStr& SensorId = SensorJson->GetObjStr("id");
		SensorNmIdH.AddDat(SensorId, SensorJson->GetObjInt("internalId"));
		SensorIdNodeIdH.AddDat(SensorId, SensorJson->GetObjInt("nodeId"));
	}

	Notify->OnNotify(TNotifyType::ntInfo, "Calling cpp constructor ...");

	return new TNodeJsRf24Radio(MyId, PinCE, PinCSN, SensorNmIdH, SensorIdNodeIdH, Notify);
}

TNodejsDHT11Sensor::TReadTask::TReadTask(const v8::FunctionCallbackInfo<v8::Value>& Args):
		TNodeTask(Args),
		JsSensor(nullptr) {
	v8::Isolate* Isolate = v8::Isolate::GetCurrent();
	v8::HandleScope HandleScope(Isolate);

	JsSensor = ObjectWrap::Unwrap<TNodejsDHT11Sensor>(Args.Holder());
}

void TNodeTask::AfterRunSync(const v8::FunctionCallbackInfo<v8::Value>& Args) {
	v8::Isolate* Isolate = v8::Isolate::GetCurrent();
	v8::HandleScope HandleScope(Isolate);

	if (!Except.Empty()) { throw Except; }

	Args.GetReturnValue().Set(WrapResult());
}