Nebula3运行时类型信息系统

Nebula3的RTTI系统允许你在运行时取得一个对象类类型并让你检查一个对象是否正是一个类的实例，或者是继承类的实例。你也可以直接从一个对象中取得类名或类fourcc标识符。所有这些功能都是在DeclareClass()和ImplementClass()背后实现的。Nebula3的RTTI机制比Nebula1和Nebula2的RTTI机制要来得更高效和更简单。

例子：

using namespace Util;
using namespace Core;

// check whether an object is instance of a specific class
if (myObj->IsInstanceOf(MyClass::RTTI))
{
// it's a MyClass object
}

// check whether an object is instance of a derived class
if (myObj->IsA(RefCounted::RTTI))
{
// it's a RefCounted instance or some RefCounted-derived instance
}

// get the class name of my object, this yields "MyNamespace::MyClass"
const String& className = myObj->GetClassName();

// get the fourcc class identifier of my object, this yields 'MYCL'
const FourCC& fourcc = myObj->GetClassFourCC();

你也可以通过中心工厂对象查询给定的类是否注册了：

using namespace Core;

// check if a class has been registered by class name
if (Factory::Instance()->ClassExists("MyNamespace::MyClass"))
{
// yep, the class exists
}

// check if a class has been registered by class fourcc code
if (Factory::Instance()->ClassExists(FourCC('MYCL')))
{
// yep, the class exists
}

原文：<<The Nebula Device 3 Document>>The Nebula3 Runtime Type Information System

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