SimpleInventory Program C++

[cokacolla]

Is there other way to solve this solution other then this one?

// A simple inventory program using a struct to store data
// in an array.


#include <cstdlib>
#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
#include <sstream>

using namespace std;

// define a data structure
struct InventoryRecord
{
  string name;   // inventory item name
  int qty;       // how many are in stock
  double cost;   // the cost
};

// const for the max size of the record array
const int MAX_SIZE = 9;

// function prototypes
void addData(InventoryRecord list[], int& size);
void dispData(const InventoryRecord list[], int size);
void saveFile(const InventoryRecord list[], int size);
void openFile(InventoryRecord list[], int& size);
char getMenuResponse();


int main(int argc, char *argv[])
{
  InventoryRecord recList[MAX_SIZE];
  int numOfRecs = 0;
  bool run = true;
  do
  {
    cout << "Inventory Program - " << numOfRecs << " items in stock" << endl;
  	switch ( getMenuResponse() ) 
  	{
	    case 'A': addData(recList, numOfRecs); break; 
  		case 'D': dispData(recList, numOfRecs); break;
  		case 'O': openFile(recList, numOfRecs); break;
  		case 'S': saveFile(recList, numOfRecs); break;
  		case 'Q': run = false; break;
  		default : cout << "That is NOT a valid choice" << endl;
  	}
  } while (run);
  cout << endl << "Program Terminated" << endl;
  
  // system("PAUSE"); // Program exits immediatly upon "Quit" if commented out
  return EXIT_SUCCESS;
}

// Task:     Allow data entry of one inventory item
// Accepts:  References to the inventory array and its size
// Returns:  Nothing
// Modifies: The array and size 'actual parameter'
// NOTE:     Could be modified to allow entry of more than one item
void addData(InventoryRecord list[], int& size)
{
  InventoryRecord tmp; // declare a temp item that we will load before putting in the array
  char response;
  char str[256]; // needed for cin.getline; we are going to use a char array
  if (size < MAX_SIZE) {
    system("cls");
    cout << "Enter Inventory Records" << endl << endl;
    cout << "Name:     ";
    // Get up to 256 characters from the keyboard including white space.
    // Stop reading if encounter the \n first. If there's any chance of 
    // more than 256 characters you will have to clean up cin with
    // cin.ignore before the next input.
    cin.getline(str, 256, '\n'); // for char arrays; different from the other getline
    tmp.name = str;
    cout << "Quantity: ";
    cin >> tmp.qty;
    cout << "Cost:     ";
    cin >> tmp.cost;
    cout << endl;
    // see if this record should be added to the array
    cout << "Add the record to inventory? (y/n) ";
    cin >> response;
    if (toupper(response) == 'Y') 
      list[size++] = tmp;
  } else {
    cout << "Inventory at full; cannot enter more unit." << endl;
    system("pause");
  }
  system("cls");
}

void dispData(const InventoryRecord list[], int size)
{
  system("cls");
  double cost = 0;
  
  if(size < 1) {
    cout << "Nothing to display" << endl;
  } else {
    cout << "All Inventory item has been shown" << endl << endl;
    cout << fixed << setprecision(2);   
    cout << "Item Name              Qty     Cost" << endl;
    cout << "~~~~~~~~~~~~~~~~~~" << endl;
        
    cout << left;     
    for (int i = 0; i < size; i++) {
      cout << setw(21) << list[i].name << right
           << setw(4)  << list[i].qty
           << setw(10) << list[i].cost << left << endl;
           cost = cost + list[i].cost * list[i].qty;
    }
    
    cout << "~~~~~~~~~~~~~~~~~~~" << endl;
    cout << right << setw(3) << size;
    cout << " items listed";
    cout << right << setw(19) << cost << endl << endl;
  }
  
  system("PAUSE");
  system("cls");
}

// Save records to disc
void saveFile(const InventoryRecord list[], int size) {
  ofstream outfi("Inventory.txt");
  
  // make sure the file stream is open before doing IO
  if (!outfi.fail()) { 
    system("cls");  
    cout << "Saving inventory to the disc ";
    
    for(int i = 0; i < size; i++) {
      outfi << list[i].name << ';' 
            << list[i].qty << ';'
            << list[i].cost;
      // Start a new line after all but the last record
      // Simplifies reading the file as EOF is at end of last line
      if (i < size-1) outfi << endl;
    }
    cout << endl << size << " records writen to the disc." << endl;
    outfi.close();
    system("PAUSE");
    system("cls");
  } 
  else {
    cout << "ERROR: problem with file" << endl;
    system("PAUSE");
    system("cls");
  }
}

// Open file and load array
void openFile(InventoryRecord list[], int& size)
{
  ifstream infi("Inventory.txt");
  string str;
  stringstream strstrm;
  
  // make sure the file stream is open before doing IO
  if (!infi.fail()) { 
  
    system("cls");
    cout << "Reading inventory from the disc ";
    
    size = 0; // overwrite any existing records
    while(!infi.eof() && size < MAX_SIZE) {
      // get and store the name
      getline(infi, str, ';'); 
      list[size].name = str;
      
      // get, convert and store the quantity
      getline(infi, str, ';');
      strstrm.str(""); strstrm.clear(); // empty and clear the stringstream
      strstrm << str; 
      strstrm >> list[size].qty;
      
      // get, convert and store the cost
      getline(infi, str); 
      strstrm.str(""); strstrm.clear(); // empty and clear the stringstream
      strstrm << str; 
      strstrm >> list[size++].cost;
    }
    cout << endl << size << " records read from the disc." << endl;
  
    system("PAUSE");
    system("cls");
  }
  else { // something went wrong with opening the file
    cout << "ERROR: problem with file" << endl;
    system("PAUSE");
    system("cls");
  }

}

char getMenuResponse()
// Task:     Put the menu on screen and get a response
// Accepts:  Nothing
// Returns:  The users response
// Modifies: Nothing
// NOTE:     Characters are far more intuitive at the command
//           line than numbers; avoid using numbers.
{
	char response;
	cout << endl << "Make your selection" << endl
		 << "(A)dd Record, (D)isplay Records, (O)pen File, (S)ave File, (Q)uit" << endl
		 << "> ";
	cin >> response;
	cin.ignore(256, '\n');	
	// clean-up up to 256 chars including the delimiter specified (\n, the endl) 
	// OR stop when the \n is encountered after removing it.
	return toupper(response);
	// note the use of toupper, why?
}

[SamuelAdams]

Nice program
What is the purpose of argv[] ?

One problem i found is if you type in a (a-z,A-Z) for the Quantity: or Cost:, the program goes into a error loop.

Another is it will allow you to enter a item without a name.

Another is when adding a item, if you type anything other than Y or y, it doesn't save when it ask Y/N

If a new item has been added, you may want to check to see if it has been saved first when they Quit.

Instead of doing a system pause when they display the inventory, I suggest you display the menu again.

when displaying the item name, you may want to limit the number of chars.
abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz really doesn't display well. I would say 30 chars or less.

If you type Enter on the menu, Quantity: or Cost: the program just goes to the next line.

Is there other way to solve this solution other then this one?

To answer your question, yes, there is always another way, depends on what you mean, or want to accomplish.

one way might be to allow them to add or display items in Inventory.txt using argv[].

argv[1] = A
would add item to inventory
so
Inventory A ItemName 10 99
would add the item to the inventory.txt file and save it.

Inventory D
argv[1] = D
would display the inventory

You could even add a search for a item name like;
Inventory D ItemName

I don't think that is what your asking, but that would allow you to create a inventory list from another process/command/batch file. Might be helpful when adding lots of items.