Introducing Classes
The only remaining feature we need to understand before solving our bookstore problem is how to write a data structure to represent our transaction data. In C++ we define our own data structure by defining a class. The class mechanism is one of the most important features in C++. In fact, a primary focus of the design of C++ is to make it possible to define class types that behave as naturally as the built-in types themselves. The library types that we've seen already, such as istream and ostream, are all defined as classesthat is,they are not strictly speaking part of the language.......
类的简介
解决书店问题之前，还需要弄明白如何编写数据结构来表示交易数据。C++ 中我们通过定义类来定义自己的数据结构。类机制是 C++ 中最重要的特征之一。事实上，C++ 设计的主要焦点就是使所定义的类类型的行为可以像内置类型一样自然。我们前面已看到的像 istream 和 ostream 这样的库类型，都是定义为类的，也就是说，它们严格说来不是语言的一部分。
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