自学教程：C++ toWebCoreString函数代码示例

bool Dictionary::getOwnPropertiesAsStringHashMap(HashMap<String, String>& hashMap) const{    if (!isObject())        return false;    v8::Handle<v8::Object> options = m_options->ToObject();    if (options.IsEmpty())        return false;    v8::Local<v8::Array> properties = options->GetOwnPropertyNames();    if (properties.IsEmpty())        return true;    for (uint32_t i = 0; i < properties->Length(); ++i) {        v8::Local<v8::String> key = properties->Get(i)->ToString();        if (!options->Has(key))            continue;        v8::Local<v8::Value> value = options->Get(key);        String stringKey = toWebCoreString(key);        String stringValue = toWebCoreString(value);        if (!stringKey.isEmpty())            hashMap.set(stringKey, stringValue);    }    return true;}

v8::Handle<v8::Value> V8MessageEvent::initMessageEventCallback(const v8::Arguments& args){    MessageEvent* event = V8MessageEvent::toNative(args.Holder());    String typeArg = toWebCoreString(args[0]);    bool canBubbleArg = args[1]->BooleanValue();    bool cancelableArg = args[2]->BooleanValue();    ScriptValue dataArg = ScriptValue(args[3]);    String originArg = toWebCoreString(args[4]);    String lastEventIdArg = toWebCoreString(args[5]);    DOMWindow* sourceArg = 0;    if (args[6]->IsObject()) {        v8::Handle<v8::Object> wrapper = v8::Handle<v8::Object>::Cast(args[6]);        v8::Handle<v8::Object> window = wrapper->FindInstanceInPrototypeChain(V8DOMWindow::GetTemplate(args.GetIsolate()));        if (!window.IsEmpty())            sourceArg = V8DOMWindow::toNative(window);    }    OwnPtr<MessagePortArray> portArray;    if (!isUndefinedOrNull(args[7])) {        portArray = adoptPtr(new MessagePortArray);        if (!getMessagePortArray(args[7], *portArray, args.GetIsolate()))            return v8::Undefined();    }    event->initMessageEvent(typeArg, canBubbleArg, cancelableArg, dataArg, originArg, lastEventIdArg, sourceArg, portArray.release());    return v8::Undefined();}

ScriptValue WorkerContextExecutionProxy::evaluate(const String& script, const String& fileName, int baseLine, WorkerContextExecutionState* state){    v8::HandleScope hs;    initContextIfNeeded();    v8::Context::Scope scope(m_context);    v8::TryCatch exceptionCatcher;    v8::Local<v8::String> scriptString = v8ExternalString(script);    v8::Handle<v8::Script> compiledScript = V8Proxy::compileScript(scriptString, fileName, baseLine);    v8::Local<v8::Value> result = runScript(compiledScript);    if (exceptionCatcher.HasCaught()) {        v8::Local<v8::Message> message = exceptionCatcher.Message();        state->hadException = true;        state->exception = ScriptValue(exceptionCatcher.Exception());        state->errorMessage = toWebCoreString(message->Get());        state->lineNumber = message->GetLineNumber();        state->sourceURL = toWebCoreString(message->GetScriptResourceName());        exceptionCatcher.Reset();    } else        state->hadException = false;    if (result.IsEmpty() || result->IsUndefined())        return ScriptValue();    return ScriptValue(result);}

static void messageHandlerInMainThread(v8::Handle<v8::Message> message, v8::Handle<v8::Value> data){    DOMWindow* firstWindow = firstDOMWindow();    if (!firstWindow->isCurrentlyDisplayedInFrame())        return;    String errorMessage = toWebCoreString(message->Get());    v8::Handle<v8::StackTrace> stackTrace = message->GetStackTrace();    RefPtr<ScriptCallStack> callStack;    // Currently stack trace is only collected when inspector is open.    if (!stackTrace.IsEmpty() && stackTrace->GetFrameCount() > 0)        callStack = createScriptCallStack(stackTrace, ScriptCallStack::maxCallStackSizeToCapture);    v8::Handle<v8::Value> resourceName = message->GetScriptResourceName();    bool shouldUseDocumentURL = resourceName.IsEmpty() || !resourceName->IsString();    String resource = shouldUseDocumentURL ? firstWindow->document()->url() : toWebCoreString(resourceName);    RefPtr<ErrorEvent> event = ErrorEvent::create(errorMessage, resource, message->GetLineNumber(), message->GetStartColumn());    // messageHandlerInMainThread can be called while we're creating a new context.    // Since we cannot create a wrapper in the intermediate timing, we need to skip    // creating a wrapper for |event|.    DOMWrapperWorld* world = DOMWrapperWorld::current();    Frame* frame = firstWindow->document()->frame();    if (world && frame && frame->script()->existingWindowShell(world)) {        v8::Local<v8::Value> wrappedEvent = toV8(event.get(), v8::Handle<v8::Object>(), v8::Isolate::GetCurrent());        if (!wrappedEvent.IsEmpty()) {            ASSERT(wrappedEvent->IsObject());            v8::Local<v8::Object>::Cast(wrappedEvent)->SetHiddenValue(V8HiddenPropertyName::error(), data);        }    }    AccessControlStatus corsStatus = message->IsSharedCrossOrigin() ? SharableCrossOrigin : NotSharableCrossOrigin;    firstWindow->document()->reportException(event.release(), callStack, corsStatus);}

void reportException(ScriptState* scriptState, v8::TryCatch& exceptionCatcher){    String errorMessage;    int lineNumber = 0;    String sourceURL;    // There can be a situation that an exception is thrown without setting a message.    v8::Local<v8::Message> message = exceptionCatcher.Message();    if (message.IsEmpty()) {        v8::Local<v8::String> exceptionString = exceptionCatcher.Exception()->ToString();        // Conversion of the exception object to string can fail if an        // exception is thrown during conversion.        if (!exceptionString.IsEmpty())            errorMessage = toWebCoreString(exceptionString);    } else {        errorMessage = toWebCoreString(message->Get());        lineNumber = message->GetLineNumber();        sourceURL = toWebCoreString(message->GetScriptResourceName());    }    // Do not report the exception if the current execution context is Document because we do not want to lead to duplicate error messages in the console.    // FIXME (31171): need better design to solve the duplicate error message reporting problem.    ScriptExecutionContext* context = getScriptExecutionContext(scriptState);    // During the frame teardown, there may not be a valid context.    if (context && !context->isDocument())        context->reportException(errorMessage, lineNumber, sourceURL);    exceptionCatcher.Reset();}

static void messageHandlerInWorker(v8::Handle<v8::Message> message, v8::Handle<v8::Value> data){    static bool isReportingException = false;    // Exceptions that occur in error handler should be ignored since in that case    // WorkerGlobalScope::reportException will send the exception to the worker object.    if (isReportingException)        return;    isReportingException = true;    // During the frame teardown, there may not be a valid context.    if (ScriptExecutionContext* context = getScriptExecutionContext()) {        String errorMessage = toWebCoreString(message->Get());        String sourceURL = toWebCoreString(message->GetScriptResourceName());        RefPtr<ErrorEvent> event = ErrorEvent::create(errorMessage, sourceURL, message->GetLineNumber(), message->GetStartColumn());        v8::Local<v8::Value> wrappedEvent = toV8(event.get(), v8::Handle<v8::Object>(), v8::Isolate::GetCurrent());        if (!wrappedEvent.IsEmpty()) {            ASSERT(wrappedEvent->IsObject());            v8::Local<v8::Object>::Cast(wrappedEvent)->SetHiddenValue(V8HiddenPropertyName::error(), data);        }        AccessControlStatus corsStatus = message->IsSharedCrossOrigin() ? SharableCrossOrigin : NotSharableCrossOrigin;        context->reportException(event.release(), 0, corsStatus);    }    isReportingException = false;}

v8::Handle<v8::Value> V8DatabaseSync::changeVersionCallback(const v8::Arguments& args){    INC_STATS("DOM.DatabaseSync.changeVersion()");    if (args.Length() < 2)        return throwError(SYNTAX_ERR);    EXCEPTION_BLOCK(String, oldVersion, toWebCoreString(args[0]));    EXCEPTION_BLOCK(String, newVersion, toWebCoreString(args[1]));    DatabaseSync* database = V8DatabaseSync::toNative(args.Holder());    RefPtr<V8SQLTransactionSyncCallback> callback;    if (args.Length() > 2) {        if (!args[2]->IsObject())            return throwError(TYPE_MISMATCH_ERR);        callback = V8SQLTransactionSyncCallback::create(args[2]);    }    ExceptionCode ec = 0;    database->changeVersion(oldVersion, newVersion, callback.release(), ec);    V8Proxy::setDOMException(ec);    return v8::Undefined();}

v8::Handle<v8::Value> V8CanvasRenderingContext2D::setShadowCallback(const v8::Arguments& args){    INC_STATS("DOM.CanvasRenderingContext2D.setShadow()");    CanvasRenderingContext2D* context = V8CanvasRenderingContext2D::toNative(args.Holder());    switch (args.Length()) {    case 3:        context->setShadow(toFloat(args[0]), toFloat(args[1]), toFloat(args[2]));        break;    case 4:        if (args[3]->IsString())            context->setShadow(toFloat(args[0]), toFloat(args[1]), toFloat(args[2]), toWebCoreString(args[3]));        else            context->setShadow(toFloat(args[0]), toFloat(args[1]), toFloat(args[2]), toFloat(args[3]));        break;    case 5:        if (args[3]->IsString())            context->setShadow(toFloat(args[0]), toFloat(args[1]), toFloat(args[2]), toWebCoreString(args[3]), toFloat(args[4]));        else            context->setShadow(toFloat(args[0]), toFloat(args[1]), toFloat(args[2]), toFloat(args[3]), toFloat(args[4]));        break;    case 7:        context->setShadow(toFloat(args[0]), toFloat(args[1]), toFloat(args[2]), toFloat(args[3]), toFloat(args[4]), toFloat(args[5]), toFloat(args[6]));        break;    case 8:        context->setShadow(toFloat(args[0]), toFloat(args[1]), toFloat(args[2]), toFloat(args[3]), toFloat(args[4]), toFloat(args[5]), toFloat(args[6]), toFloat(args[7]));        break;    default:        V8Proxy::throwError(V8Proxy::SyntaxError, "setShadow: Invalid number of arguments");        break;    }    return v8::Undefined();}

void V8ConsoleMessage::handler(v8::Handle<v8::Message> message, v8::Handle<v8::Value> data){    // Use the frame where JavaScript is called from.    Frame* frame = V8Proxy::retrieveFrameForEnteredContext();    if (!frame)        return;    Page* page = frame->page();    if (!page)        return;    v8::Handle<v8::String> errorMessageString = message->Get();    ASSERT(!errorMessageString.IsEmpty());    String errorMessage = toWebCoreString(errorMessageString);    v8::Handle<v8::StackTrace> stackTrace = message->GetStackTrace();    RefPtr<ScriptCallStack> callStack;    // Currently stack trace is only collected when inspector is open.    if (!stackTrace.IsEmpty() && stackTrace->GetFrameCount() > 0)        callStack = createScriptCallStack(stackTrace, ScriptCallStack::maxCallStackSizeToCapture);    v8::Handle<v8::Value> resourceName = message->GetScriptResourceName();    bool useURL = resourceName.IsEmpty() || !resourceName->IsString();    String resourceNameString = useURL ? frame->document()->url() : toWebCoreString(resourceName);    V8ConsoleMessage consoleMessage(errorMessage, resourceNameString, message->GetLineNumber());    consoleMessage.dispatchNow(page, callStack);}

v8::Handle<v8::Value> V8DOMStringMap::namedPropertySetter(v8::Local<v8::String> name, v8::Local<v8::Value> value, const v8::AccessorInfo& info){    INC_STATS("DOM.DOMStringMap.NamedPropertySetter");    ExceptionCode ec = 0;    V8DOMStringMap::toNative(info.Holder())->setItem(toWebCoreString(name), toWebCoreString(value), ec);    if (ec)        return throwError(ec, info.GetIsolate());    return value;}

void V8XSLTProcessor::removeParameterMethodCustom(const v8::FunctionCallbackInfo<v8::Value>& args){    if (isUndefinedOrNull(args[1]))        return;    XSLTProcessor* imp = V8XSLTProcessor::toNative(args.Holder());    String namespaceURI = toWebCoreString(args[0]);    String localName = toWebCoreString(args[1]);    imp->removeParameter(namespaceURI, localName);}

v8::Handle<v8::Value> V8Clipboard::setDataCallback(const v8::Arguments& args){    INC_STATS("DOM.Clipboard.setData()");    Clipboard* clipboard = V8Clipboard::toNative(args.Holder());    if (args.Length() != 2)        return throwError("setData: Invalid number of arguments", V8Proxy::SyntaxError);    String type = toWebCoreString(args[0]);    String data = toWebCoreString(args[1]);    return v8Boolean(clipboard->setData(type, data));}

v8::Handle<v8::Value> V8XSLTProcessor::removeParameterMethodCustom(const v8::Arguments& args){    if (isUndefinedOrNull(args[1]))        return v8::Undefined();    XSLTProcessor* imp = V8XSLTProcessor::toNative(args.Holder());    String namespaceURI = toWebCoreString(args[0]);    String localName = toWebCoreString(args[1]);    imp->removeParameter(namespaceURI, localName);    return v8::Undefined();}

v8::Handle<v8::Value> V8DOMStringMap::namedPropertySetter(v8::Local<v8::String> name, v8::Local<v8::Value> value, const v8::AccessorInfo& info){    INC_STATS("DOM.DOMStringMap.NamedPropertySetter");    v8::Handle<v8::Value> property = info.Holder()->GetRealNamedPropertyInPrototypeChain(name);    if (!property.IsEmpty())        return value;    if (info.Holder()->HasRealNamedCallbackProperty(name))        return value;    ExceptionCode ec = 0;    V8DOMStringMap::toNative(info.Holder())->setItem(toWebCoreString(name), toWebCoreString(value), ec);    if (ec)        return throwError(ec);    return value;}

v8::Handle<v8::Value> V8XSLTProcessor::setParameterCallback(const v8::Arguments& args){    INC_STATS("DOM.XSLTProcessor.setParameter");    if (isUndefinedOrNull(args[1]) || isUndefinedOrNull(args[2]))        return v8::Undefined();    XSLTProcessor* imp = V8XSLTProcessor::toNative(args.Holder());    String namespaceURI = toWebCoreString(args[0]);    String localName = toWebCoreString(args[1]);    String value = toWebCoreString(args[2]);    imp->setParameter(namespaceURI, localName, value);    return v8::Undefined();}

// Concatenates "args" to a string. If args is empty, returns empty string.// Firefox/Safari/IE support non-standard arguments to document.write, ex://   document.write("a", "b", "c") --> document.write("abc")//   document.write() --> document.write("")static String writeHelperGetString(const v8::Arguments& args){    String str = "";    for (int i = 0; i < args.Length(); ++i)        str += toWebCoreString(args[i]);    return str;}

v8::Local<v8::Value> V8WorkerContextEventListener::callListenerFunction(ScriptExecutionContext* context, v8::Handle<v8::Value> jsEvent, Event* event){    V8GCController::checkMemoryUsage();    v8::Local<v8::Function> handlerFunction = getListenerFunction(context);    v8::Local<v8::Object> receiver = getReceiverObject(context, event);    if (handlerFunction.IsEmpty() || receiver.IsEmpty())        return v8::Local<v8::Value>();    InspectorInstrumentationCookie cookie;    if (InspectorInstrumentation::timelineAgentEnabled(context)) {        String resourceName("undefined");        int lineNumber = 1;        v8::ScriptOrigin origin = handlerFunction->GetScriptOrigin();        if (!origin.ResourceName().IsEmpty()) {            resourceName = toWebCoreString(origin.ResourceName());            lineNumber = handlerFunction->GetScriptLineNumber() + 1;        }        cookie = InspectorInstrumentation::willCallFunction(context, resourceName, lineNumber);    }    v8::Handle<v8::Value> parameters[1] = { jsEvent };    V8RecursionScope recursionScope(context);    v8::Local<v8::Value> result = handlerFunction->Call(receiver, 1, parameters);    InspectorInstrumentation::didCallFunction(cookie);    return result;}

static v8::Handle<v8::Value> v8HTMLAudioElementConstructorCallback(const v8::Arguments& args){    INC_STATS("DOM.HTMLAudioElement.Contructor");    if (!args.IsConstructCall())        return throwError("DOM object constructor cannot be called as a function.");    Frame* frame = V8Proxy::retrieveFrameForCurrentContext();    if (!frame)        return throwError("Audio constructor associated frame is unavailable", V8Proxy::ReferenceError);    Document* document = frame->document();    if (!document)        return throwError("Audio constructor associated document is unavailable", V8Proxy::ReferenceError);    // Make sure the document is added to the DOM Node map. Otherwise, the HTMLAudioElement instance    // may end up being the only node in the map and get garbage-collected prematurely.    toV8(document);    String src;    if (args.Length() > 0)        src = toWebCoreString(args[0]);    RefPtr<HTMLAudioElement> audio = HTMLAudioElement::createForJSConstructor(document, src);    V8DOMWrapper::setDOMWrapper(args.Holder(), &V8HTMLAudioElementConstructor::info, audio.get());    audio->ref();    V8DOMWrapper::setJSWrapperForDOMNode(audio.get(), v8::Persistent<v8::Object>::New(args.Holder()));    return args.Holder();}

v8::Handle<v8::Value> V8Custom::v8HTMLAudioElementConstructorCallback(const v8::Arguments& args){    INC_STATS("DOM.HTMLAudioElement.Contructor");    if (!args.IsConstructCall())        return throwError("DOM object constructor cannot be called as a function.");    Frame* frame = V8Proxy::retrieveFrameForCurrentContext();    if (!frame)        return throwError("Audio constructor associated frame is unavailable", V8Proxy::ReferenceError);    Document* document = frame->document();    if (!document)        return throwError("Audio constructor associated document is unavailable", V8Proxy::ReferenceError);    // Make sure the document is added to the DOM Node map. Otherwise, the HTMLAudioElement instance    // may end up being the only node in the map and get garbage-ccollected prematurely.    V8DOMWrapper::convertNodeToV8Object(document);    RefPtr<HTMLAudioElement> audio = new HTMLAudioElement(HTMLNames::audioTag, document);    audio->setAutobuffer(true);    if (args.Length() > 0) {        audio->setSrc(toWebCoreString(args[0]));        audio->scheduleLoad();    }    V8DOMWrapper::setDOMWrapper(args.Holder(), V8ClassIndex::ToInt(V8ClassIndex::NODE), audio.get());    audio->ref();    V8DOMWrapper::setJSWrapperForDOMNode(audio.get(), v8::Persistent<v8::Object>::New(args.Holder()));    return args.Holder();}

void V8AbstractEventListener::invokeEventHandler(v8::Handle<v8::Context> v8Context, Event* event, v8::Handle<v8::Value> jsEvent){    // We push the event being processed into the global object, so that it can be exposed by DOMWindow's bindings.    v8::Local<v8::String> eventSymbol = v8::String::NewSymbol("event");    v8::Local<v8::Value> returnValue;    // In beforeunload/unload handlers, we want to avoid sleeps which do tight loops of calling Date.getTime().    if (event->type() == "beforeunload" || event->type() == "unload")        DateExtension::get()->setAllowSleep(false);    {        // Catch exceptions thrown in the event handler so they do not propagate to javascript code that caused the event to fire.        v8::TryCatch tryCatch;        tryCatch.SetVerbose(true);        // Save the old 'event' property so we can restore it later.        v8::Local<v8::Value> savedEvent = v8Context->Global()->GetHiddenValue(eventSymbol);        tryCatch.Reset();        // Make the event available in the global object, so DOMWindow can expose it.        v8Context->Global()->SetHiddenValue(eventSymbol, jsEvent);        tryCatch.Reset();        // Call the event handler.        tryCatch.SetVerbose(false); // We do not want to report the exception to the inspector console.        returnValue = callListenerFunction(jsEvent, event);        if (!tryCatch.CanContinue())            return;        // If an error occurs while handling the event, it should be reported.        if (tryCatch.HasCaught()) {            reportException(0, tryCatch);            tryCatch.Reset();        }        // Restore the old event. This must be done for all exit paths through this method.        tryCatch.SetVerbose(true);        if (savedEvent.IsEmpty())            v8Context->Global()->SetHiddenValue(eventSymbol, v8::Undefined());        else            v8Context->Global()->SetHiddenValue(eventSymbol, savedEvent);        tryCatch.Reset();    }    if (event->type() == "beforeunload" || event->type() == "unload")        DateExtension::get()->setAllowSleep(true);    ASSERT(!V8Proxy::handleOutOfMemory() || returnValue.IsEmpty());    if (returnValue.IsEmpty())        return;    if (!returnValue->IsNull() && !returnValue->IsUndefined() && event->storesResultAsString())        event->storeResult(toWebCoreString(returnValue));    // Prevent default action if the return value is false;    // FIXME: Add example, and reference to bug entry.    if (m_isAttribute && returnValue->IsBoolean() && !returnValue->BooleanValue())        event->preventDefault();}

void V8PannerNode::distanceModelAttrSetterCustom(v8::Local<v8::String> name, v8::Local<v8::Value> value, const v8::AccessorInfo& info){    PannerNode* imp = V8PannerNode::toNative(info.Holder());#if ENABLE(LEGACY_WEB_AUDIO)        if (value->IsNumber()) {        bool ok = false;        uint32_t model = toUInt32(value, ok);        ASSERT(ok);        if (!imp->setDistanceModel(model))            throwError(v8TypeError, "Illegal distanceModel", info.GetIsolate());        return;    }#endif    if (value->IsString()) {        String model = toWebCoreString(value);        if (model == "linear" || model == "inverse" || model == "exponential") {            imp->setDistanceModel(model);            return;        }    }        throwError(v8TypeError, "Illegal distanceModel", info.GetIsolate());}