C++ connect many headers to one and use those headers functions

Question

guys, I have a question, I don't know how can I connect many headers in one header, let's call it "Master header" and use functions from that headers, for example

// A.h
#include <iostream>

class A {
public:
  A();
  void showMessage(string msg);
};

// B.h
class B {
public:
  B();
  void CountMessages()
};

// C.h
#include "A.h"
#include "B.h"

class C : public B, public A {
public:
  C();
  void DoSomething();
}

and I want to call function CountMessages from class 'b' using a class an object of class 'c' and/or a class 'a', like

//c.cpp
#include "C.h"
#include "B.h"    
#include "A.h"

extern A b_obj;
extern B a_obj;

C::DoSomething() {
  b_obj.CountMessages();
  a_obj.showMessage("Hello");
}

possible duplicate of [C++ class forward declaration](http://stackoverflow.com/questions/9119236/c-class-forward-declaration) — deviantfan, Jan 18 '15 at 19:00

score 1 · Answer 1 · answered Jan 18 '15 at 19:07

I have a question, I don't know how can I connect many headers in one header, let's call it "Master header" and use functions from that headers,

Create the file and add #include lines for all the other header files.

MasterHeader.h:

#include "A.h"
#include "B.h"
#include "C.h"

c.cpp:

#include "MasterHeader.h"

Caution: I wouldn't recommend this practice in general. This is useful only if the interface provided by "MasterHeader.h" is primary, with "A.h","B.h", and"C.h" serving the purpose of ease of maintenance.

well, "C.h" is that "MasterHeader.h", so I should just include it into any cpp file and call all that functions, that I need ? — Nazar Zebrovich, Jan 18 '15 at 19:12

C++ connect many headers to one and use those headers functions

1 Answers1