array based database not working correctly - c++

Question

I have to write a program for an array based database that will allow the user to enter new data, update existing data, delete entries and view a list of the entries. The requirements are a structure called DATE, a structure called CustData that holds the user data, an array of type CustData with a size of 10 and requires an individual function for entering, updating, deleting and displaying the customer data. It also needs to use a while loop to initialize each index in the array with everything initialized to 0. I have a rough program written but the more I work on it the more I feel like I am doing it completely wrong. So far I have it working to the point that it lets me add multiple entries without overwriting previous ones, but I can't seem to be able to limit the number of entries I can input. I also have the displaying of entries correct. Any help that could be offered is greatly appreciated, below is my program so far, with some of the data input sections commented out to make testing it easier. My apologies for leaving this out, this is in C++, written with visual studio 2013.
#include <iostream>
#include <fstream>
#include <iomanip>
#include <string>
using namespace std;
struct Date
{
int month,
day,
year;
};
struct cust
{
int ID;
string name;
string address;
string city;
string state;
string zip;
string phone;
double balance;
Date lastpayment;
};
const int SIZE = 10;
int menuchoice;
int num = 0;
int i;
void showmenu();
void funcentercustdata(cust[], int);
void funcupdatecustdata();
void funcdeletecustdata();
void funcdisplaycustdata(cust[], int);
cust custdb[SIZE];
int main()
{
cout << "Welcome to Michael's Marvelous Database Contrabulator!\n";
cout << setw(10) << "Customer Database\n\n\n";
showmenu();
int index;
for (index = 0; index < SIZE; index++)
{
custdb[index].ID = 0;
custdb[index].name = "";
custdb[index].address = "";
custdb[index].city = "";
custdb[index].state = "";
custdb[index].zip = "";
custdb[index].phone = "";
custdb[index].balance = 0.00;
custdb[index].lastpayment.month = 0;
custdb[index].lastpayment.day = 0;
custdb[index].lastpayment.year = 0;
}
return 0;
}
void showmenu()
{
cout << "\n\n1) Enter new customer data.\n";
cout << "2) Update customer data.\n";
cout << "3) Delete customer data.\n";
cout << "4) Display Customer data.\n";
cout << "5) Quit the program.\n\n";
cout << "Please enter your choice: ";
cin >> menuchoice;
do
{
switch (menuchoice)
{
case 1:
funcentercustdata(custdb, SIZE);
showmenu();
break;
case 2:
funcupdatecustdata();
showmenu();
break;
case 3:
funcdeletecustdata();
showmenu();
break;
case 4:
funcdisplaycustdata(custdb, SIZE);
showmenu();
break;
case 5:
cout << "Thank you and have a nice day!\n";
break;
default:
cout << "Please enter a correct choice\n";
cin >> menuchoice;
break;
}
} while (menuchoice != 5);
}
void funcentercustdata(cust custinfo[], int size)
{
if (custinfo[i].ID != 0)
{
i++;
cout << "\n\nEnter ID: ";
cin >> custinfo[i].ID;
cout << "Enter name: ";
cin.ignore(0);
cin >> custinfo[i].name;
/* cout << "Enter address: ";
cin.ignore(0);
cin>>custinfo[i].address;
cout << "Enter city: ";
cin.ignore(0);
cin>>custinfo[i].city;
cout << "Enter state: ";
cin.ignore(0);
cin>>custinfo[i].state;
cout << "Enter zip: ";
cin.ignore(0);
cin>>custinfo[i].zip;
cout << "Enter phone number (###-###-####): ";
cin.ignore(0);
cin>>custinfo[i].phone;
cout << "Enter balance: ";
cin >> custinfo[i].balance;
cout << "Enter last payment (mo day year, e.g. 11 17 2014): ";
cin >> custinfo[i].lastpayment.month >> custinfo[i].lastpayment.day
>> custinfo[i].lastpayment.year;
cin.ignore(1);
// }*/
cout << "Customers successfully added.\n";
}
else if (custinfo[i].ID != 0 && custinfo[i].ID >= 4)
{
cout << "No further inputs allowed\n";
}
else
{
cout << "\n\nEnter ID: ";
cin >> custinfo[i].ID;
cout << "Enter name: ";
cin.ignore(0);
cin >> custinfo[i].name;
/* cout << "Enter address: ";
cin.ignore(0);
cin>>custinfo[i].address;
cout << "Enter city: ";
cin.ignore(0);
cin>>custinfo[i].city;
cout << "Enter state: ";
cin.ignore(0);
cin>>custinfo[i].state;
cout << "Enter zip: ";
cin.ignore(0);
cin>>custinfo[i].zip;
cout << "Enter phone number (###-###-####): ";
cin.ignore(0);
cin>>custinfo[i].phone;
cout << "Enter balance: ";
cin >> custinfo[i].balance;
cout << "Enter last payment (mo day year, e.g. 11 17 2014): ";
cin >> custinfo[i].lastpayment.month >> custinfo[i].lastpayment.day
>> custinfo[i].lastpayment.year;
cin.ignore(1);
// }*/
cout << "Customers successfully added.\n";
}
}
void funcupdatecustdata()
{
cout << "insert function 2\n\n";
}
void funcdeletecustdata()
{
cout << "insert function 3\n\n";
}
void funcdisplaycustdata(cust custinfo[], int size)
{
for (int i = 0; i < size; i++)
{
if (custinfo[i].ID == 0)
cout << " ";
else if (custinfo[i].ID != 0)
{
cout << "\n\nClient ID: " << custinfo[i].ID << endl;
cout << "Client name: " << custinfo[i].name << endl;
/* cout << "Client address: " << custinfo[i].name << endl;
cout << "Client city: " << custinfo[i].name << endl;
cout << "Client state: " << custinfo[i].name << endl;
cout << "Client zip: " << custinfo[i].name << endl;
cout << "Client phone: " << custinfo[i].name << endl;*/
cout << "Client balance: " << custinfo[i].balance << endl;
cout << "Client last deposit: " << custinfo[i].lastpayment.month << "/" <<
custinfo[i].lastpayment.day << "/" << custinfo[i].lastpayment.year << endl;
}
}
}

Answer 1

You've asked multiple questions concerning the issues in your program. So I will look at the first question:
I can't seem to be able to limit the number of entries I can input
First, your code has some fundamental flaws. One flaw is the repeated calling of showmenu() while you're in the showmenu() function. This is a recursive call, and is totally unnecessary. Imagine if your program or similar program that was structured this way had to be running 24 hours a day, and there were thousands of entries added. You will evenutally blow out the stack with all the recursive calls. So this has to be fixed.
Second, showmenu(), at least to me, should do what it says, and that is "show the menu". It should not be processing input. Do the processing of input in a separate function.
Here is a more modularized version of the program:
#include <iostream>
void processChoice(int theChoice);
void showmenu();
void addCustomer();
void deleteCustomer();
int getMenuChoice();
int customerCount = 0;
int main()
{
cout << "Welcome to Michael's Marvelous Database Contrabulator!\n";
cout << setw(10) << "Customer Database\n\n\n";
int choice = 0;
do
{
showmenu();
choice = getMenuChoice();
if (choice != 5)
processChoice(choice);
} while (choice != 5);
}
void showmenu()
{
cout << "\n\n1) Enter new customer data.\n";
cout << "2) Update customer data.\n";
cout << "3) Delete customer data.\n";
cout << "4) Display Customer data.\n";
cout << "5) Quit the program.\n\n";
}
int getMenuChoice()
{
int theChoice;
cout << "Please enter your choice: ";
cin >> theChoice;
return theChoice;
}
void processChoice(int theChoice)
{
switch (theChoice)
{
case 1:
addCustomer();
break;
//...
case 3:
deleteCustomer();
break;
}
}
void addCustomer()
{
if ( customerCount < 10 )
{
// add customer
// put your code here to add the customer
//...
// increment the count
++customerCount;
}
}
void deleteCustomer()
{
if ( customerCount > 0 )
{
// delete customer
--customerCount;
}
}
This is the basic outline of keeping track of the number of customers. Code organization and modularity is the key. The count of the current number of entries is either incremented or decremented wihin the addCustomer and deleteCustomer functions. Also note the test that is done in add/deleteCustomer().
In the main() function, note the do-while loop and the way it is set up. The showMenu function shows itself, the getMenuChoice function gets the choice and returns the number that was chosen.
If the choice is not 5, process the request. If it is 5, then the while part of the do-while kicks you out of the processing, otherwise you start back at the top (showMenu, getMenuChoice, etc). This avoids the recursive calls that your original code was doing.