CArray ERROR with pointers in VC++ 1

[Noelia]

This code compile:

////////////////////////////////////////
MyObject.h
////////////////////////////////////////

class MyObject : public CObject
{
public:
MyObject();
~MyObject();
};

////////////////////////////////////////
MyObject.cpp
////////////////////////////////////////

#include "stdafx.h"
#include "myObject.h"

MyObject::MyObject()
{
}
MyObject::~MyObject()
{
}

////////////////////////////////////////
MyClass.h
////////////////////////////////////////

#include <afxtempl.h>
#include &quot;MyObject.h&quot;
class MyClass : public CObject
{
private:
CArray<MyObject*, MyObject*> arrObject; (1)
public:
MyClass();
~MyClass();
void AddObject( MyObject* Object ); (2)
};

////////////////////////////////////////
MyClass.cpp
////////////////////////////////////////

#include &quot;stdafx.h&quot;
#include &quot;myobject.h&quot;

MyClass::MyClass()
{
}

MyClass::~MyClass()
{
}

void MyClass::AddObject( MyObject* Object ) (3)
{
arrObject.Add( Object );
}



Case One:
------------------------------------------------------------------

If I replace the lines with number for the next lines

CArray<MyObject, MyObject*> arrObject; (1)
void AddObject( MyObject* Object ); (2)
void MyObject::AddObject( MyObject* Object ) (3)

or this

CArray<MyObject, MyObject&> arrObject; (1)
void AddObject( MyObject& Object ); (2)
void MyObject::AddObject( MyObject& Object ) (3)


the code NOT compile, and in both cases the error is:
&quot;MyObject' : 'operator =' function is unavailable
\\vc98\mfc\include\afxtempl.h(1567) : while compiling class-template member function
'void __thiscall CArray<class MyObject,class MyObject *>::SetAtGrow(int,class MyObject *)'&quot;


Case Two:
------------------------------------------------------------------

If I replace the lines with number for the next lines

CArray<MyObject, MyObject> arrObject; (1)
void AddObject( MyObject Object ); (2)
void MyObject::AddObject( MyObject Object ) (3)

the code NOT compile, and the error is:
&quot;No copy constructor available for class 'MyObject'&quot;

even if the copy constructor is added the error is still reported.

 

[Ordinary]

Noelia,

This is very interesting but what exactly is your question?

 

[Noelia]

The question is &quot;Why not compile in the cases 1 or 2?&quot;

 

[IonelBurtan]

I had exactlly your problem and the cause is:

1. in internal manipulation of the arguments you give to CArray it needs the =operator and copy contructor of the class you pass as argument.

2.The default =operator and copy constructor for a CObject derived class ARE NOT AVAILABLE because the are declared PRIVATE in CObject.

Provide =operator and copy constructor for your class derived from CObject and the code will work.

Hope this helps,s-) Blessed is he who in the name of justice and good will, shepards the week through the valley of darknees...

http://home.domaindlx.com/ionelb

 

[Guest_imported]

What do mean exactly with
Provide =operator and copy constructor for your class derived from CObject and the code will work.

Must i add to my Array-class ther Operator = and :: Copy

 

[IonelBurtan]

//////declaration MyObject.h//////////////////////////
class MyObject : public CObject
{
public:
MyObject();
MyObject(MyObject& ob) //copy contructor
MyObject& operator=(MyObject& ob); //operator=
~MyObject();
};

//////implementation MyObject.cpp//////////////////////////
MyObject::MyObject(MyObject& ob)
{
m_membervariabile=ob.m_membervariabile
......
m_last_membervariabile=ob.m_last_membervariabile
}
MyObject& MyObject:perator=(MyObject& ob)
{
this->m_membervariabile=ob.m_membervariabile
.......
this->m_last_membervariabile=ob.m_last_membervariabile
return *this;
}

Also read the article &quot;BUG: Error C2664 and C2582 While Using CArray Class&quot; from MSDN(I have April 2001) to understand better the problem.

I remember I had this problem too, and it took me two weeks to realize it at that time.

This should help you,
s-)

Blessed is he who in the name of justice and good will, shepards the week through the valley of darknees...

http://www20.brinkster.com/ionelb