编程参考 - Rule of Three and the Rule of Five in C++

C++ 中的 "三规则 "和 "五规则 "是管理类中资源管理函数（特殊成员函数）的准则。这些规则有助于确保类正确一致地管理动态内存、文件句柄或网络连接等资源。

The Rule of Three and the Rule of Five in C++ are guidelines for managing the resource management functions (special member functions) in a class. These rules help ensure that classes manage resources like dynamic memory, file handles, or network connections correctly and consistently.

Rule of Three

"三原则"指出，如果一个类定义了以下内容之一，那么它可能应该明确定义所有三项内容：

The Rule of Three states that if a class defines one of the following, it should probably explicitly define all three:

1, Destructor

2, Copy Constructor

3, Copy Assignment Operator

之所以会出现这条规则，是因为如果一个类管理一个资源（如动态内存），编译器提供的这些函数的默认实现可能无法正确处理该资源，从而导致重复删除或资源泄漏等问题。

This rule arises because if a class manages a resource (like dynamic memory), the default implementations of these functions provided by the compiler mig