MFC Syntax set Node as new Node

Question

Ive got a little question to my Syntax. I made this Struct

struct Node
{
    CString name;
    CString vorname;
    CString geburtsdatum;
    CString adresse;
    CString plz;
    CString ort;
    CString email;
    CString geschlecht;
    CString land;
    CString firma;
    CString telefon;
    CString fax;
    Node* next;
    Node* previous;
};
Node *Actual;
const Node *Start;

So, this is in my .h File. Now I want into my .cpp File that Start is a new Node It should be something this way Start = new Node;

Can you tell me the Syntax to do that?

Thanks

Answer 1

Since your variable is const, you could not modify it's content. I guess you'd like to have an ability to modify them but still keep pointer (Start) as const. The next code will do it.

// .h file
...
extern Node* const Start;

// .cpp file
Node* const Start = new Node();
int main()
{
    Start->name = "user2675121";
    delete Start;
    return 0;
}

Keyword 'extern' used with 'Start' (int .h file) tells compiler that this variable will be initialized somewhere else. And const should be placed after '*' to make a pointer (not its data) const. But using a global variables is always a bad decision.

Answer 2

I presume you are trying to do the following in your cpp file. start = new Node();

in that case why 'const node* start'. Making const, will not allow new data to be written on that variable.

My suggestion is removed 'const'

#include <stdio.h>
struct Node
{
    int info;
    Node* next;
    Node* previous;
};
int main()
{
    const Node* start ;
    int d = 4;
    start = new Node();
    start->info = d;
    printf("%d\t", start->info);

    return 0;
}

In this, at start->info says "Node::info readonly"..ie you can't assign structure data on start . So kindly remove const and do necessary operations