如何将类类型映射到C ++中的类的实例？ [英] How can I map class types to instances of that class in C++?

问题描述

我希望有一个从类到每个类的实例的映射。目标是具有用于基于组件的游戏引擎的组件的容器，其中对象可以具有每个组件类型的至多一个。

I wish to have a map from classes to instances of each class. The goal is to have a container of components for a component-based game engine where an object can have at most one of each component type.

在Java中，我只能使用类对象作为键。如何在C ++中做类似的事情？我最初的研究建议像使用typeid（component_instance）.name（）作为键。

In Java, I could just use class objects as the key. How can I do something similar in C++? My initial research suggests something like using typeid(component_instance).name() as the key. Is there a better way to do this?

推荐答案

与更多动态语言（如Python或Java）不同，C ++中的类不是对象他们自己。在运行时它们根本不存在（就程序员的观点而言）。

Unlike in more dynamic languages like Python or Java, classes in C++ are not objects themselves. At runtime they merely do not exist (as for a programmers point of view).

您的 typeid 但是对于性能问题，我会使用哈希或数字ID（类似于在类中定义为静态的整数）而不是字符串。

Your typeid approach is not that bad, but for performance issues I'd use a hash or a numeric ID (like an integer defined as static in your class) instead of the string.

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