如何访问 c++ 中的 class 变量

Question

Is it possible in c++ to access class variables in other classes without creating an object. I have tried to use static, but the other class doesnt recognize my variable. I have 3 classes. In two of those the sae variables should be used. In the third class I am changing the values. Would be grateful if you could help. Maybe youve got an example.

Answer 1

class Myclass
{

    public:
         static int i;
};

int Myclass::i = 10;


class YourClass
{

    public:
        void doSomething()
        {
             Myclass::i = 10;  //This is how you access static member variables
        }

};

int main()
{
    YourClass obj;
    obj.doSomething();
    return 0;
}

Answer 2

static is the right keyword here:

class A {
public:
  static int i; // <-- this is a class variable
};

class B {
public:
  void f() { A::i = 3; } // <-- this is how you access class variables
};

They only potential problem I can think of is that

1. You made the class variable protected or private , thus rendering it inaccessible from other code.
2. You forgot to specify the full scope of the class variable (with A:: in this example).

Answer 3

I think the Singleton Pattern would help, but I'm no big fan of it. A lot better design would be to have one class take ownership of the object, and pass references to this object to the other classes.

Answer 4

yes you can bro, try this

struct car{

        string model;
        string paint;
        int price;


           };


         int main(){

          // creates an object of the class car

            car BMW;

          // assign the values
           bmw.model = "m sports";
            bmw.paint ="red";
            bmw.price = 24000;


              }