Table of contents
1. Empty class
1. What is it?
If a class does not explicitly define any members, it is simply called an empty class.
class A {};//一个空类
2. A member in an empty class?
Is there really nothing in the empty class?
No, when any class does not write anything, the compiler will automatically generate 6 default member functions.
(Default member function: The member function automatically generated by the compiler is called the default member function if the user does not explicitly implement it)
Two, 6 default member functions
Default member function: The member function that is automatically generated by the compiler without being explicitly implemented by the user is called the default member function.
1) Constructor: Initialize the member variables in the object when the object is created.
2) Destructor: Complete the destruction of the object.
3) Copy constructor: With this function, objects of the same type can be initialized to create objects.
4) Assignment overload function: With this function, one object can be assigned to another object.
5) Overloaded function for taking addresses of ordinary objects: mainly for taking addresses of ordinary objects, which is rarely implemented by itself.
6) Overload function for taking address of const object: mainly to take address of const object, which is rarely realized by itself.
