Array of class objects

**Elysia** · 03-26-2008

The question becomes, what you do want to do with them?

**GCNDoug** · 03-26-2008

I guess i need to do all of the work that was originally done in main through the class functions now?

Well I need to display all of the items with a number in order to select them. Then work with them like I was doing with the built in items in my original code.

**Elysia** · 03-26-2008

You could overload functions that returns the private data so you can display it.

**GCNDoug** · 03-26-2008

That sounds awesome I would love to make all of that information no longer private although I'm not sure that's what I'm suppose to do.

I need to be able to access the information in the switch statement and others... I guess I do need it to be free data; not sure if that's what my teacher wants though. Oh well, I just want it to work after with your help I was able to make the array of class objects.

Is overloading ok to do?

**Elysia** · 03-26-2008

You don't need to make it public.
Just make member functions that returns the data you need.

**GCNDoug** · 03-26-2008

Like this?

Code:

#include <string>
#include <iostream>

class dispenserType
{
	public:
		int getNoOfItems() const;
		int getCost() const;
		void makeSale();
		dispenserType(int setNoOfItems = 50, int setCost = 50);
		void read(std::ifstream& readfrom)
		{
			readfrom >> name;
			readfrom >> numberOfItems;
			readfrom >> cost;
		}
		void return(std::string& heldname int& heldnoi int& heldcost)
		{
			heldname = name;
			heldnoi = numberOfItems;
			heldcost = cost;
		}
	private:
		std::string name;
		int numberOfItems;
		int cost;
};

then would (in main) productlist[0].heldname give me the first held name?! I think I'm getting close!

or should I make a function to return each different variable and be like

std::string returnname()

Code:

{
    std::string heldname;
    heldname = name

   return name;
}

can I return a string?

productlist[0].returnname

**Elysia** · 03-26-2008

Originally Posted by GCNDoug

Like this?

Maybe...
But what if you don't want all 3 of them?
Better create 3 functions, each that returns said part of the data you need.

then would (in main) productlist[0].heldname give me the first held name?!

No, it wouldn't (at least if I'm interpreting this correctly). All you're doing is defining a member function that takes an std::string reference named heldname as argument. You need to pass in a variable of type std::string to the function which will then, upon return of the function, have the information you want.

**GCNDoug** · 03-26-2008

Code:

#include <string>
#include <iostream>

class dispenserType
{
	public:
		int getNoOfItems() const;
		int getCost() const;
		void makeSale();
		dispenserType(int setNoOfItems = 50, int setCost = 50);
		void read(std::ifstream& readfrom)
		{
			readfrom >> name;
			readfrom >> numberOfItems;
			readfrom >> cost;
		}
		std::string returnname(std::string heldname)		
		{
			heldname = name;
			return heldname;
		}
		int returnnoi(int noi)
		{
			noi = numberOfItems;
			return noi;
		}
		int returncost (int& heldcost)
		{
			heldcost = cost;
			return cost;
		}
	private:
		std::string name;
		int numberOfItems;
		int cost;
};

Code:

while (choice !=99)
	{
		switch (choice)
		{
		case 1:
			sellProduct (productlist[0].returnname(name), counter);
			break;
		case 2:
			sellProduct (productlist[1].returnname(name), counter);
			break;
		case 3:
			sellProduct (productlist[2].returnname(name), counter);
			break;
		case 4:
			sellProduct (productlist[3].returnname(name), counter);
			break;
		case 5:
			sellProduct (productlist[4].returnname(name), counter);
			break;
		case 6:
			sellProduct (productlist[5].returnname(name), counter);
			break;
		case 7:
			sellProduct (productlist[6].returnname(name), counter);
			break;
		case 8:
			sellProduct (productlist[7].returnname(name), counter);
			break;
		case 9:
			sellProduct (productlist[8].returnname(name), counter);
			break;
		default:
			cout << "Invalid selection." << endl;
}

1>c:\users\doug\documents\visual studio 2008\projects\lab5candy\lab5candy\candymachinelab. cpp(66) : error C2664: 'sellProduct' : cannot convert parameter 1 from 'std::string' to 'dispenserType []'
1> No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called

lol

**Elysia** · 03-26-2008

Come on. This is obvious.
sellProduct takes a dispenserType array.
You need to think about your implementation. What do you want and where?

And as for this:

Code:

		std::string returnname(std::string heldname)		
		{
			heldname = name;
			return heldname;
		}
		int returnnoi(int noi)
		{
			noi = numberOfItems;
			return noi;
		}
		int returncost (int& heldcost)
		{
			heldcost = cost;
			return cost;
		}

You are returning the data, so it does not need to take an argument.

Code:

		std::string returnname()		
		{
			return heldname;
		}

**GCNDoug** · 03-26-2008

I want the name lol! I fixed the class functions though. Will keep working on the other stuff thanks again for ur help!
void sellProduct(dispenserType product[], cashRegister& pCounter);
dispenserType productlist[8];

productlist is a dispenserType

Code:

#include <string>
#include <iostream>

class dispenserType
{
	public:
		int getNoOfItems() const;
		int getCost() const;
		void makeSale();
		dispenserType(int setNoOfItems = 50, int setCost = 50);
		void read(std::ifstream& readfrom)
		{
			readfrom >> name;
			readfrom >> numberOfItems;
			readfrom >> cost;
		}
		std::string returnname()		
		{
			return name;
		}
		int returnnoi()
		{
			return numberOfItems;
		}
		int returncost()
		{
			return cost;
		}
	private:
		std::string name;
		int numberOfItems;
		int cost;
};

**GCNDoug** · 03-26-2008

Well after I fixed the class functions it says this for every line of the switch statement.

1>c:\users\doug\documents\visual studio 2008\projects\lab5candy\lab5candy\candymachinelab. cpp(62) : error C2660: 'dispenserType::returnname' : function does not take 1 arguments
Have to fun to class though thanks for the help I hope i can figure it out later

**Elysia** · 03-26-2008

Look,
if dispenserType::returnname does not take any arguments, then don't pass any arguments to it.

**GCNDoug** · 03-26-2008

already tried, if I take it out it still gives a compiler error.

Code:

		case 1:
			sellProduct (productlist[0].returnname, counter);
			break;

1>c:\users\doug\documents\visual studio 2008\projects\lab5candy\lab5candy\candymachinelab. cpp(62) : error C3867: 'dispenserType::returnname': function call missing argument list; use '&dispenserType::returnname' to create a pointer to member

**Elysia** · 03-26-2008

As the error says, it's a function, not a variable.
Functions must have () at the end, otherwise it's illegal. If it were a non-class function, you would have taken its address instead.

**GCNDoug** · 03-26-2008

I am pretty sure that I tried it earlier with the () but I'm not sure will post results when I get a chance to compile again

Thread: Array of class objects

Thread Tools

Search Thread

Display

Similar Threads

File handling with Array filled with a class

Unknown Memory Leak in Init() Function

Quick question about SIGSEGV

Type and nontype parameters w/overloading

Struct *** initialization