What is a class pattern and what is an object pattern in C

I've been looking at this model recently, so I'll explain it according to the content in it.

Purpose: Tell the adapter the specialrequest of the adaptee, the customer only pays attention to the target, and the target asks the customer's needs through the adapter.

Class mode: Adapter is privately inherited by the adapter. (The difference between public inheritance and private inheritance is that the inheritance class of private inheritance inherits from the protected of the parent class and becomes private.)

In this case, public inheritance can also be dropped) The target object calls the Request method of the adapter, and the Request method calls the SpecialRequest.

Object Mode: The adapter constructs an adapter object inside the constructor. The target object calls the Adapter request method, and the request method calls the member function that has been assigned to the Adaptive object, and this member function directly calls the specialrequest.

In fact, you don't need to be too entangled in the concept, when you don't understand the process, the concept is very vague, when you understand the process, you will find that the concept is very profound.

For example, if any car is composed of engine, chassis, body, wheels, etc., then the class is the basic properties of all cars (in this case, the parts of the car) and the object is a specific car (it can be BMW, other brands, etc.).

So in a nutshell, a class is a basic property (abstract) that all objects have in common, and an object that contains a concrete existence of these properties (is concrete).

In layman's terms, "person" is a concept, that is, a class, and a specific person, such as Zhang San and Li Si, is a specific individual of a person, that is, the object of the "human" class. That is, classes and objects are the relationship between concepts and concrete instances.

Definition of C++ class:

A class is a blueprint or prototype that defines the variables and methods of all objects of the same class.

Classes can also define class variables and class methods. You can access class variables and methods from an instance of a class or directly from a class. A class method can only manipulate class variables and does not have to access instance variables or instance methods.

The first time the system encounters a class in a program, it creates copies of all of its class variables for that class, and all instances of the class share its class variables.

Definition of a C++ object:

Defining a class is equivalent to creating a new class type. To use a class, you must also use the class you have defined to describe its instance variables (i.e., objects). In C++, once a class type is defined, its instance variable (object) can be created, initialized, and a pointer variable can be defined to point to it.

A class, instantiated, is an object.

In C++, struct and class are essentially the same, the only difference is that struct is public by default, class is private by default, and it needs to be declared public when public; There is also the struct in C, which cannot contain functions and inheritance, while C++ can contain functions and inherit from other classes.

A class is an abstraction of some actual objects with the same properties or some common characteristics, for example, a car is a class, an object is an instantiation of a class, an object is an actual object, a car is an object, a truck is an object, and an armored car is an object.

A message is a method of a class, a class is a declaration, an abstraction, and an object is a concrete entity.

For example, the light bulb is a class, the energy-saving lamp is the object, the switch of the light is the message, and you press it to send him a message to turn on.

For example: apple-like.

Subject: The apple you are holding in your hand.

As for the news... Looks like it's used in software development... I don't belong to any language.

It seems to be a response mechanism, the operation generates a message, and the system executes it step by step through the message queue... It seems so).

Message refers to the data information exchanged between different classes, which you can understand as a text message sent when two people communicate.

A class is an object-oriented formulation introduced in C++, where a class represents a set of related variable methods. Since a class is a declaration, an abstraction, it cannot be used. So there is the concept of objects.

For example, the dog is a class, which includes the function of eating, and the concept of mouth .........But you can't use the word dog to describe a dog, but you have to use the object, such as creating an object called "Wangcai" with this class, which is a dog.

Methods of classes are those that are declared by static methods with the keyword static.

Object methods are, of course, non-static, not declared with static keywords.

In addition to being encapsulated, classes in C++ are also meant to be defined to be as easy to understand as built-in types (e.g., ints, etc.). Examples:

#include

class a constructor of class a, with an int variable aprivate:

int n;A member variable of the class.

main()

In C++, classes encapsulate member functions and member variables, etc., and only by defining the object of the class can the member functions of the class be called, and the number is the initialization value of the defined object.

A class is like an engineering prototype, and an object is like a car, and one engineering prototype can make multiple cars.

Just like an identifier, as long as you have an object name, you can access the data in memory that the object name points to! It's about adding names to the data! It's equivalent to your name, which identifies you as a person!

class student ;int main() assumes that the program rolls quietly as above, then stu can be said to be the object of the class.

My understanding is that a class means a category or a kind, and the object is a specific individual in the class. So the relationship between class and object is the relationship between the whole and the individual. Humans, for example, are classes. One by one, you, me, and his specific people are the objects in this category.

C++ is not a fully object language, so there are two types of value types and object types.

You should be talking about the member variables in the class, and the object of the class is the instantiation of the class, and defining a class is actually an abstract class.

For example, if you define a class called a car, then the BMW car is the object of the class, an instantiation of the class. The object you define has all the properties and methods of the class. And you're talking about member variables in the class.

Each instance object you define owns that variable (property).

An object is an instance of a non-primitive type, and a variable is an instance of a primitive type, such as int, float, double, bool, long, etc.