Usage of class in c++

Class is a blueprint in C that encapsulates data and functionality. Its members include: Data members: variables that store data. Method: A function that defines a class operation or behavior. Object: An instance created from a class that has all the data members and methods in the class.

Usage of class in C

What is class?
Class is a blueprint in C that encapsulates data and functionality. It allows the creation of object instances with specific properties and methods.

Class syntax:

<code class="cpp">class class_name {
    // 类的数据成员（变量）
    data_member1;
    data_member2;
    // 类的方法（函数）
    method1();
    method2();
};</code>

Members of the class:
Data members: Data stored in the class variable.
Method: Function of the operation or behavior defined in the class.

Object of class:
Instance created from class. The object has all the data members and methods defined in the class.

Constructor of class:
Special method called when creating an object, used to initialize the data members of the object.

Destructor of class:
Special method called when the object is destroyed to release occupied resources.

Class access control:
Controls the visibility of class members to external code. There are three access control levels:

• #public: can be accessed within the class and outside the class.
• protected: Can be accessed within the class, derived classes and friend classes.
• private: Can only be accessed within the class.

Class usage example:

<code class="cpp">class Person {
public:
    string name;  // 数据成员
    void greet() {  // 方法
        cout << "Hello, my name is " << name << endl;
    }
};

int main() {
    Person john;  // 创建对象 john
    john.name = "John Doe";  // 访问数据成员
    john.greet();  // 调用方法
    return 0;
}</code>

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