Comapre Two diff data members

[ronak]

class member
{
public:
int mcode;
void min()
{
cout<<"\nMcode:\t";
cin>>mcode;
}
};

class product:public member
{
public:
int pcode;
void pin()
{
cout<<"\nPcode:\t";
cin>>pcode;
}
void pout()
{
int mas;
mas=m.mcode;
cout<<mas;
cout<<endl;

if(pcode==mas)
cout<<"True";
else
cout<<"False";
}
};

void main()
{
clrscr();

member m;
product p;

m.min();
p.pin();
p.pout();

getch();
}




Guys i hav created two different classes with data member Pcode,mcode.
I want to compare these data member. i am able to do so in void main but unable to perform the task using a function. So pls help me

[screw]

Hi!

The purpose of a class is that you can hide the data member and attach the function (which can operate with hidden data members.) So it is rewarding make private data members.

class example
{
 int m; // default access level is private

public:
 int getMember(){return m;} // You can access the member with getMember() and setMember
 void setMember(int a){m = a;}

};

If you make any variable, object in a scope, then you can't access them from other scope. Therefore you get error at this line:

mas=m.mcode;


You should make a similar code:

int main()
{
	member m;
	product p;
	
	if (m.getMember() == p.getMember())
	{
		cout << "They are equal" << endl;
	}
	else cout << "They aren't equal" << endl;
	
	return 0;
}

(of course you need put #include <iostream> and using namespace std; at the beginning of your code)


The other solution is that you use operator overloading technology so you can use == operator between objects.

http://www.devhood.com/tutorials/tutorial_details.aspx?tutorial_id=502

http://www.google.com/search?hl=hu&q=c%2B%2B+operator+overloading&btnG=Keres%C3%A9s&lr=

[ronak]

Thnks buddy for the reply. But my problem is yet unsolved.

Bro i am using TURBO C++ 3.0.

Problem:
Actually there are two classes named product and sales. i want to compare the data variables. I knw hw to do it by using formal argunments but i want to do without using it

void sales::sin()
{
clrscr();

cout<<"Customers Name:\t";
puts(billname);

cout<<"\n\nProduct Code:\t";
cin>>scode;

//Actually I want to do the folowing:
if(sales::scode == product::code)
{
strcpy(sales::sname,product::name);
cout<<sales::sname;

sales::srate=product::rate;
cout<<sales::srate;

start:
cout<<"Quantity:\t";
cin>>sales::qty;
if(sales::qty > product::stock)
{
cout<<"\nOut of Stock";
cout<<"\nEnter Again";
goto start;
cout<<"\n";
}

cout<<"Total:\t";
total=srate*qty;
}

cout<<"Wrong Product code entered";
}


The full program code is here:

#include<iostream.h>
#include<conio.h>
#include<dos.h>
#include<stdio.h>
#include<fstream.h>
#include<string.h>

class product
{
public:
	void pin();
	void pout();
	void pedit();
//private:
	double rate;
	double stock;
	double code;
	char name[50];
};

class member
{
public:
	void min();
	void mout();
	void medit();
	void mcard();
//private:
	char memname[50];
	int no;
	char add[75];
	char tel[25];
	double card;
	long double amt;
};

class sales: public product
{
public:
	void sin();
	void sout();
//private:
	double scode;
	double qty;
	char sname[50];
	double srate;
	double total;

};

char billname[50];

void member::min()
{

	clrscr();

	int q;

	fstream m;

	m.open("member.dat", ios::in | ios::binary);
	m.seekg(0,ios::end);
	q=m.tellg()/sizeof(member);
	q+=1000;
	m.close();

	m.open("member.dat", ios::in | ios::app | ios::binary);

	char x;

	do
	{
		clrscr();
		cout<<"\nEnter Members Detail:\n\n";
		cout<<"Name:\t";
		gets(memname);
		cout<<"Card No:\t";
		cin>>card;
		cout<<"Address:\t";
		gets(add);
		cout<<"Tel:\t";
		cin>>tel;
		cout<<"Amount Deposit:\tRs";
		cin>>amt;
		cout<<"Member No:\t";
		no=q++;
		cout<<no;
		no++;

		m.write((char*)this,sizeof(member));

		cout<<"\n\nEnter More(Y/N)?";
		x=getch();
	}while(x=='y' || x=='Y');

	cout<<"No";
	m.close();
}


void member::mout()
{
	clrscr();

	fstream m;
	m.open("member.dat", ios::in | ios::binary);

	m.read((char*)this,sizeof(member));

	cout<<"\nMembers Detail:\n";

	while(!m.eof())
	{
		cout<<"\n\nName:\t";
		puts(memname);
		cout<<"\nCard Number\t";
		cout<<card;
		cout<<"\nAddress:\t";
		puts(add);
		cout<<"Tel\t";
		cout<<tel;
		cout<<"\nAmount Deposit:\t";
		cout<<amt;
		cout<<"\nMember No:\t";
		cout<<no;

		m.read((char*)this,sizeof(member));
	}

	m.close();
}

void member::medit()
{
	clrscr();
	fstream m;
	m.open("member.dat" ,ios::in | ios::out | ios::binary);

	int p=0, loc, buff=0;

	int x,xa;
	cout<<"\nMember No:\t";
	cin>>x;

	m.read((char*)this,sizeof(member));

	while(!m.eof())
	{
		if(x==no)
		{
			buff=100;
			break;
		}
		p++;
		m.read((char*)this,sizeof(member));
	}

	loc=p*sizeof(member);
	m.seekp(loc);

	if(buff!=0)
	{
		cout<<"\n\nCurrent Detail:\n\n";
		cout<<"Name:\t";
		puts(memname);
		cout<<"\nCard Number\t";
		cout<<card;
		cout<<"\nAddress:\t";
		puts(add);
		cout<<"Tel\t";
		cout<<tel;
		cout<<"\nAmount Deposit:\t";
		cout<<amt;
		cout<<"\nMember No:\t";
		cout<<no;

		cout<<"\n\n\nEnter Members Detail:\n\n";

		cout<<"Name:\t";
		gets(memname);
		cout<<"Card No:\t";
		cin>>card;
		cout<<"Address:\t";
		gets(add);
		cout<<"Tel:\t";
		cin>>tel;
		cout<<"Amount Deposit:\tRs";
		cin>>amt;
		cout<<"Member No:\t";
		cout<<no;

		m.write((char*)this,sizeof(member));
	}

	else

	cout<<"Data MisMatached";

	cout<<"\n\nMore Modification(Y/N)?";
	xa=getch();
	if(xa=='y' || xa=='Y')
	{
		cout<<"Yes";
		medit();
	}
	else
	cout<<"No";

	m.close();
}

void product::pin()
{

	clrscr();

	int q;

	fstream f;

	f.open("product.dat", ios::in | ios::binary);
	f.seekg(0,ios::end);
	q=f.tellg()/sizeof(product);
	q+=1000;
	f.close();

	f.open("product.dat", ios::in | ios::app | ios::binary);

	char x;

	do
	{
		clrscr();
		cout<<"\nEnter Products Detail:\n\n";
		cout<<"Name:\t";
		gets(name);
		cout<<"Rate:\tRs ";
		cin>>rate;
		cout<<"Stock:\t";
		cin>>stock;
		cout<<"Code:\t";
		code=q++;
		cout<<code;
		code++;

		f.write((char*)this,sizeof(product));

		cout<<"\n\nEnter More(Y/N)?";
		x=getch();
	}while(x=='y' || x=='Y');

	cout<<"No";
	f.close();
}


void product::pout()
{
	clrscr();

	fstream f;
	f.open("product.dat", ios::in | ios::binary);

	f.read((char*)this,sizeof(product));

	cout<<"\nProducts Detail:\n";

	while(!f.eof())
	{

		cout<<"\n\nName:\t";
		puts(name);
		cout<<"Rate:\tRs ";
		cout<<rate;
		cout<<"\nStock:\t";
		cout<<stock;
		cout<<"\nCode:\t";
		cout<<code;

		f.read((char*)this,sizeof(product));
	}

	f.close();
}

void product::pedit()
{
	clrscr();
	fstream f;
	f.open("product.dat" ,ios::in | ios::out | ios::binary);

	int p=0, loc, buff=0;

	int x,xa;
	cout<<"\nProducts Code:\t";
	cin>>x;

	f.read((char*)this,sizeof(product));

	while(!f.eof())
	{
		if(x==code)
		{
			buff=100;
			break;
		}
		p++;
		f.read((char*)this,sizeof(product));
	}

	loc=p*sizeof(product);
	f.seekp(loc);

	if(buff!=0)
	{
		cout<<"\n\nCurrent Detail:\n\n";
		cout<<"Name:\t";
		puts(name);
		cout<<"Rate:\tRs ";
		cout<<rate;
		cout<<"\nStock:\t";
		cout<<stock;
		cout<<"\nCode:\t";
		cout<<code;

		cout<<"\n\n\nEnter Products Detail:\n\n";

		cout<<"Name:\t";
		gets(name);
		cout<<"Rate:\tRs ";
		cin>>rate;
		cout<<"Stock:\t";
		cin>>stock;
		cout<<"Code:\t";
		cout<<code;

		f.write((char*)this,sizeof(product));
	}

	else

	cout<<"Data MisMatached";

	cout<<"\n\nMore Modification(Y/N)?";
	xa=getch();

	if(xa=='y' || xa=='Y')
	{
		cout<<"Yes";
		pedit();
	}

	else
	cout<<"No";

	f.close();
}

void member::mcard()
{
	clrscr();

	char x;
	int cardnum,memnum,check=1;
	cout<<"Are you Member(Y/N)";
	x=getch();

	if(x=='y' || x=='Y')
	{
		cout<<"Yes";
		cout<<"\n\n\tMember no:\t";
		cin>>memnum;
		cout<<"\tCard no:\t";
		cin>>cardnum;

		fstream m;
		m.open("member.dat", ios::in | ios::binary);

		m.read((char*)this,sizeof(member));

		while(!m.eof())
		{
			if(memnum==no && cardnum==card)
			{
				check=0;
				strcpy(billname,memname);
				break;
			}
			m.read((char*)this,sizeof(member));
		}

		if(check!=0)
		{
			cout<<"\nWrong Info Enterd";
			cout<<"\n\nTry Again:\t";
			x=getch();
			if(x=='y' || x=='Y')
			{
				cout<<"Yes";
				mcard();
			}
			else
			cout<<"No";
			goto end;
		}

	}

	else
	{
		cout<<"No";
		cout<<"\n\n\tName:\t";
		gets(billname);
	}

	sales s;
	s.sin();

	end:
}

void sales::sin()
{
	clrscr();

	cout<<"Customers Name:\t";
	puts(billname);

	cout<<"\n\nProduct Code:\t";
	cin>>scode;

       //Actually I want to do the folowing:
		if(sales::scode == product::code)
		{
			strcpy(sales::sname,product::name);
			cout<<sales::sname;

			sales::srate=product::rate;
			cout<<sales::srate;

			start:
			cout<<"Quantity:\t";
			cin>>sales::qty;
			if(sales::qty >  product::stock)
			{
				cout<<"\nOut of Stock";
				cout<<"\nEnter Again";
				goto start;
				cout<<"\n";
			}

			cout<<"Total:\t";
			total=srate*qty;
		}

		cout<<"Wrong Product code entered";
}

void mainmenu()
{

	clrscr();
	int x;
	char xx;

	product p;
	member m;
	sales s;

	cout<<"Main Menu\n\n";

	cout<<"Products\n";
	cout<<"\t\t1.Add New Products\n";
	cout<<"\t\t2.View Existing Products\n";
	cout<<"\t\t3.Modify Existing Prodcuts\n";

	cout<<"\nMembers\n";
	cout<<"\t\t4.Add New Members\n";
	cout<<"\t\t5.View Existing Members\n";
	cout<<"\t\t6.Modify Existing Members\n";

	cout<<"\nBilling\n";
	cout<<"\t\t7.Billing\n";

	cout<<"\n\tEnter Choice:\t";

	cin>>x;

	switch(x)
	{

		case 1:
		p.pin();
		break;

		case 2:
		p.pout();
		break;

		case 3:
		p.pedit();
		break;

		case 4:
		m.min();
		break;

		case 5:
		m.mout();
		break;

		case 6:
		m.medit();
		break;

		case 7:
		m.mcard();
		break;
	 }

	cout<<"\n\nBack to Main Menu(Y/N)?\t";
	xx=getch();

	if(xx=='y' || xx=='Y')
	{
		cout<<"Yes";
		mainmenu();
	}
	else
	{
		cout<<"No";
		cout<<"\nBye! Will Meet Soon!";
	}

}

void main()
{
	clrscr();
	mainmenu();
	getch();
}

[screw]

Here is a problem:

if(sales::scode == product::code)
{
strcpy(sales::sname,product::name);
cout<<sales::sname;
...

You have to refer for the members by . or -> symbols
For example:

if (sales.scode == product.code)
{
strcpy(sales.sname,product.name);


(You can refer to members with using :: but the data and function members are releated to class and not object. So here you should use . symbol)