How do you explain C++ pointers to a C#/Java developer? [closed]

Answer 1

References in C# act the same way as pointers in C++, without all the messy syntax.

Consider the following C# code:

public class A
{
    public int x;
}

public void AnotherFunc(A a)
{
    a.x = 2;
}

public void SomeFunc()
{
    A a = new A();
    a.x = 1;

    AnotherFunc(a);
    // a.x is now 2
}

Since classes are references types, we know that we are passing an existing instance of A to AnotherFunc (unlike value types, which are copied).

In C++, we use pointers to make this explicit:

class A
{
public:
    int x;
};

void AnotherFunc(A* a) // notice we are pointing to an existing instance of A
{
    a->x = 2;
}

void SomeFunc()
{
    A a;
    a.x = 1;

    AnotherFunc(&a);
    // a.x is now 2
}