Declaring variables

Applications Programming
1

Hey guys im facing a problem in declaring variables. i have a few classes like the one below...

#ifndef _FINANCE_H
#define    _FINANCE_H

#include <string>
#include <iostream>
#include <fstream>
#include <stdlib.h>

using namespace std ;


class  readStraitsTimesIndex
{
    public:
         void StraitsTimesIndex(fstream&) ;
    private:
};

class readDow
{
    public:
        void Dow(fstream&) ;
    private:
 };

[/CODE]
what i am trying to do is to use a value which is being the output of one of the class class and to be displayed into the other class. I tried using an object member like the one below ,

class  readStraitsTimesIndex
{
    public:
         void StraitsTimesIndex(fstream&) ;
String value ;
    private:

};

[/CODE]

and then assigned a value to it, but it will only work within the class. how do i go about saving a certain variable and using it in all the classes

2

What do you mean by 'using it in all the classes'? Anywhere you have a readStraitsTimesIndex object you have access to its 'value' member. You must be creating the object sometime for that code to get called at all, right?

3

What i meant is, for example... i run a class and it gives me an output of "abc". i would then want to use this output to be displayed in a seperate class. What i tried was...

class  readStraitsTimesIndex
{
    public:
         void StraitsTimesIndex(fstream&) ;
String value ;
    private:
};

i put the output of "abc" into value. and then in the cpp of the other class, i tried to read it out. but all it gave me was a blank. I do not think i can make it public as i have to use the value given to me by the running of the 1st class

4

Objects don't work that way. They don't transfer between themselves magically, you have to give them some way to do so. There's a lot of ways.

class MyClass
{
public:
        MyClass() { value=4; }

        getValue() { return(value); }

        int value;
};

class OtherClass
{
public:
        void use_result_obj(const MyClass &my)
        {
                cout << "value=" << my.value << "\n";
        }

        void use_result_int(int value)
        {
                cout << "value=" << value << "\n";
        }
};

int main(void)
{
        MyClass a;
        OtherClass b;

        // generate result in a.value
        a.some_function();

        // one way to transfer
        b.use_result_obj(a);
        // another way
        b.use_result_int(a.value);
        // yet another way
        b.use_result_int(a.getValue());
        return(0);
}

You might want to review some basic C++.