C++ HTMLCollection::namedItem方法代码示例

v8::Handle<v8::Value> V8HTMLCollection::callAsFunctionCallback(const v8::Arguments& args)
{
    INC_STATS("DOM.HTMLCollection.callAsFunction()");
    if (args.Length() < 1)
        return v8::Undefined();

    HTMLCollection* imp = V8HTMLCollection::toNative(args.Holder());

    if (args.Length() == 1)
        return getItem(imp, args[0]);

    // If there is a second argument it is the index of the item we want.
    String name = toWebCoreString(args[0]);
    v8::Local<v8::Uint32> index = args[1]->ToArrayIndex();
    if (index.IsEmpty())
        return v8::Undefined();

    unsigned current = index->Uint32Value();
    Node* node = imp->namedItem(name);
    while (node) {
        if (!current)
            return toV8(node);

        node = imp->nextNamedItem(name);
        current--;
    }

    return v8::Undefined();
}

JSValue JSHTMLCollection::nameGetter(ExecState* exec, JSValue slotBase, PropertyName propertyName)
{
    JSHTMLCollection* collection = jsCast<JSHTMLCollection*>(asObject(slotBase));
    const AtomicString& name = propertyNameToAtomicString(propertyName);
    HTMLCollection* impl = collection->impl();
#if ENABLE(MICRODATA)
    if (impl->type() == ItemProperties)
        return toJS(exec, collection->globalObject(), static_cast<HTMLPropertiesCollection*>(impl)->propertyNodeList(name));
#endif
    return toJS(exec, collection->globalObject(), impl->namedItem(name));
}

// HTMLCollections are strange objects, they support both get and call,
// so that document.forms.item(0) and document.forms(0) both work.
static EncodedJSValue JSC_HOST_CALL callHTMLCollection(ExecState* exec)
{
    if (exec->argumentCount() < 1)
        return JSValue::encode(jsUndefined());

    // Do not use thisObj here. It can be the JSHTMLDocument, in the document.forms(i) case.
    JSHTMLCollection* jsCollection = static_cast<JSHTMLCollection*>(exec->callee());
    HTMLCollection* collection = jsCollection->impl();

    // Also, do we need the TypeError test here ?

    if (exec->argumentCount() == 1) {
        // Support for document.all(<index>) etc.
        bool ok;
        UString string = exec->argument(0).toString(exec);
        unsigned index = Identifier::toUInt32(string, ok);
        if (ok)
            return JSValue::encode(toJS(exec, jsCollection->globalObject(), collection->item(index)));

        // Support for document.images('<name>') etc.
        return JSValue::encode(getNamedItems(exec, jsCollection, Identifier(exec, string)));
    }

    // The second arg, if set, is the index of the item we want
    bool ok;
    UString string = exec->argument(0).toString(exec);
    unsigned index = Identifier::toUInt32(exec->argument(1).toString(exec), ok);
    if (ok) {
        String pstr = ustringToString(string);
        Node* node = collection->namedItem(pstr);
        while (node) {
            if (!index)
                return JSValue::encode(toJS(exec, jsCollection->globalObject(), node));
            node = collection->nextNamedItem(pstr);
            --index;
        }
    }

    return JSValue::encode(jsUndefined());
}

// HTMLCollections are strange objects, they support both get and call,
// so that document.forms.item(0) and document.forms(0) both work.
static JSValue JSC_HOST_CALL callHTMLCollection(ExecState* exec, JSObject* function, JSValue, const ArgList& args)
{
    if (args.size() < 1)
        return jsUndefined();

    // Do not use thisObj here. It can be the JSHTMLDocument, in the document.forms(i) case.
    JSHTMLCollection* jsCollection = static_cast<JSHTMLCollection*>(function);
    HTMLCollection* collection = jsCollection->impl();

    // Also, do we need the TypeError test here ?

    if (args.size() == 1) {
        // Support for document.all(<index>) etc.
        bool ok;
        UString string = args.at(0).toString(exec);
        unsigned index = string.toUInt32(&ok, false);
        if (ok)
            return toJS(exec, jsCollection->globalObject(), collection->item(index));

        // Support for document.images('<name>') etc.
        return getNamedItems(exec, jsCollection, Identifier(exec, string));
    }

    // The second arg, if set, is the index of the item we want
    bool ok;
    UString string = args.at(0).toString(exec);
    unsigned index = args.at(1).toString(exec).toUInt32(&ok, false);
    if (ok) {
        String pstr = string;
        Node* node = collection->namedItem(pstr);
        while (node) {
            if (!index)
                return toJS(exec, jsCollection->globalObject(), node);
            node = collection->nextNamedItem(pstr);
            --index;
        }
    }

    return jsUndefined();
}

v8::Handle<v8::Value> V8HTMLCollection::namedPropertyGetter(v8::Local<v8::String> name, const v8::AccessorInfo& info)
{
    if (!info.Holder()->GetRealNamedPropertyInPrototypeChain(name).IsEmpty())
        return v8Undefined();
    if (info.Holder()->HasRealNamedCallbackProperty(name))
        return v8Undefined();

    HTMLCollection* imp = V8HTMLCollection::toNative(info.Holder());
#if ENABLE(MICRODATA)
    if (imp->type() == ItemProperties) {
        if (!static_cast<HTMLPropertiesCollection*>(imp)->hasNamedItem(toWebCoreAtomicString(name)))
            return v8Undefined();
        RefPtr<PropertyNodeList> item = static_cast<HTMLPropertiesCollection*>(imp)->propertyNodeList(toWebCoreAtomicString(name));
        if (!item)
            return v8Undefined();
        return toV8(item.release(), info.Holder(), info.GetIsolate());
    }
#endif
    Node* item = imp->namedItem(toWebCoreAtomicString(name));
    if (!item)
        return v8Undefined();
    return toV8(item, info.Holder(), info.GetIsolate());
}