This is probably simple but... Class A : public B When creating a class A B''s constructor didn''t get called (I think). Is there something I need to do to make sure it gets kicked off? Many thanks Chris

B's constructor will always be called, before executing the body of A's constructor.

A simple program to show the constructor sequence is the following:

#include <iostream>using namespace std;class B{public: B() { cout << "B::B()" << endl; } virtual ~B() { cout << "B::~B()" << endl; }};class A : public B{public: A() { cout << "A::A()" << endl; } ~A() { cout << "A::~A()" << endl; }};intmain(){ A a; return 0;}

When compiled and executed, this will give the following output:

B::B()
A::A()
A::~A()
B::~B()

HTH

Edited by - JungleJim on May 8, 2001 8:01:15 AM

Edited by - JungleJim on May 8, 2001 8:02:03 AM

If you have a constructor that needs parameters, you call it like so;

class B{public: B(int i) { };};class A : public B{ A(int i) : B(i) { };};

Just the same as parameter initialisation.

class _2dpoint
{
public:
int x, y;
_2dpoint(int nx, int ny)
{
x = nx;
y = ny;
}
};

class _3dpoint : public _2dpoint
{
public:
int z;
_3dpoint(int nx, int ny, int nz) : _2dpoint(nx, ny)
{
z = nz;
}
};

hope you get the point

Arkon
[QSoft Systems]