How to describe objects in c++

There are two ways to describe objects in C: Reference: Create an alias of the object, and changing the object pointed to by the reference will change the state of the original object. Pointer: Create an alias that points to the memory address of an object. Changing the object pointed to by the pointer will change the state of the original object.

Describing objects in C

In C, an object is an instance of a class, which holds the Class-defined state and behavior. There are two main ways to describe an object:

1. Using a reference

When you use a reference to describe an object, an alias for the object is created. Changing the object pointed to by a reference will actually change the state of the original object. The syntax is as follows:

<code class="cpp">class MyClass {
    public:
        int x;
};

int main() {
    MyClass object1;
    MyClass &object2 = object1;  // 创建引用

    object2.x = 10;  // 通过引用更改对象状态
    cout << object1.x << endl;  // 输出 10，因为对象1和对象2指向同一对象
}</code>

2. Using pointers

When using pointers to describe objects, an alias of the memory address of the object will be created. Changing the pointer to an object actually changes the state of the original object. The syntax is as follows:

<code class="cpp">class MyClass {
    public:
        int x;
};

int main() {
    MyClass object1;
    MyClass *object2 = &object1;  // 创建指针

    object2->x = 10;  // 通过指针更改对象状态
    cout << object1.x << endl;  // 输出 10，因为 object2 指向 object1
}</code>

Choose to use references or pointers

In most cases, it is recommended to use references because they are safer and more efficient than pointers. However, using pointers is necessary when you need to deal with empty objects or when you need to perform low-level operations on objects (for example, memory management).

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