'm_dlgColor' : undeclared identifier in B.cpp error....

Hey,

Good day.


In my project.

A.h

Code:

...

Public:

COLORREF     m_dlgColor;

...

A.cpp
......

B.h
...
B.cpp

Code:

#include "A.h"

...

m_dlgColor = RGB(90,90,90);

...

I already declared m_dlgColor as a public propertise. and i also include A.h to my B.cpp.
Why i can't compile the project successful ?

Thanks!

Novice's question. :-)

A member of a class is just that: a member. It doesn't exist on its own, but only as part of a ... whatever you defined it as part of.

As you said,
Does i should declare "COLORREF m_dlgColor;" at B.h too?

Suppose, when i changed A.cpp class member - m_dlgColor value to (200, 200, 200). I still want to change B.cpp class member - m_dlgColor value to (200, 200, 200) synchronized.

Then, how?

thanks!

Colour of what?

You need something like this.

Code:

class foo {
Public:

COLORREF     m_dlgColor;
};

And you need an OBJECT instance of some sort

Code:

foo aThingamajig;

before you can do

Code:

aThingamajig.m_dlgColor = RGB(90,90,90);

Let's think about classes again:

Code:

class bob {
    public:
        int m_int;
        void bob_function(void);
};

Given this class, there is no possible way that "m_int" by itself could ever possibly be correct, except inside the member function bob_function. Everywhere else, it must be object.m_int.

i guess i already understand what you said. thanks!
And furthermore questions.

A.h

Code:

Public:
COLORREF   m_dlgColor;

// declare the member at head file.

A.cpp
[code]
class ObjectA {
public:
int m_intA;
// Q1, What's the different Or reason, if i declare member of "m_dlgColor" here ?
void bob_functionA(void);
};



B.h

Code:

Public:
COLORREF   m_dlgColorObjectB;

B.cpp

Code:

class ObjectB {
    public:
        int m_intB;
        void bob_functionB(void);
        {
         // Q2: try to initialization Or Asign value via the following statement ?
         m_dlgColorObjectB = ObjectA.m_dlgColor
        }
        
};

Q3. Does the bob_functionB() Could be filled outside of Class ObjectB? What's the different between fill the member function inside the class or outside of the class?

:-)

Originally Posted by Salem

Colour of what?

My windowns forms application skin color changed....

Neither of your questions make any sense. We declared our ints in the same place, so asking the difference based on where they're located isn't meaningful. And of course you can never assign anything inside a class definition -- you don't have any objects to assign values to. You initialize values in the constructor.

Really stupid questions.

i am appricated for you patient. :-)

Thanks a lot.