c++ - 指向结构错误CDCDCD的C++结构指针

Question

struct XYZ {
    XYZ *adress;
};

XYZ *Ex;
int main() {
    Ex = new XYZ[3];
    Ex->adress = (++Ex);
    cout << Ex->adress << endl;
    Ex->adress = (++Ex);
    cout << Ex->adress << endl;
    Ex->adress = (--Ex)->adress;
    cout << Ex->adress << endl;    

输出:

0105E424        0105E4280105E424

struct XYZ {
    XYZ *adress;
};

XYZ *Ex;

void copy_adress(XYZ *Ex) {
    Ex->adress = (++Ex);
}

int main() {
    Ex = new XYZ[3];
    copy_adress(Ex);
    cout << Ex->adress << endl;
    Ex->adress = (++Ex);
    cout << Ex->adress << endl;
    Ex->adress = (--Ex)->adress;
    cout << Ex->adress << endl;

输出:

CDCDCDCD
00A3E53C
CDCDCDCD

您能告诉我为什么会这样吗，以及我该如何解决？

Answer 1

当您将指针复制或传递给函数时，指针的行为就像常规对象一样。对副本所做的更改不会反射(reflect)在原件中。为了使函数中的更改可见，您需要引用以下内容:

void copy_adress(XYZ *&Ex) {
   Ex->adress = (++Ex);
}

现在，这两个版本是等效的。