We're going to do an inventory management system. In the real world, this would use a database, not a file. Inventory contains

• item names (or description), like "socks, - red" or "socks - blue". Thius has to be a character string that WILL include spaces.
• item numbers that are unique to the item, similar to UPC codes, like 121821 or 128122. These are usually character strings.
• a price, like 4.99, a double.
• a quantity on hand, like 13, an integer.

Your code need to have the following features, all accessible from a menu.

• Add a new inventory item to the data in memory. You'll type in the inventory number, description, quantity and price. This will also update the number of items on the menu screen.
• List the inventory on the screen in neat columns. Display it in chucks of 15 items with a pause in between.
• Search the inventory for an item by inventory number. If found, print the stored info, otherwise print 'not found'.
• Calculate the total value on hand. The sum is the accumulation of all the (quantities * prices).
• Save what's in memory to the disk
• Overwrite what's in memory from the disk

The way your work this is you'll load a file, add, search, etc, then write it back to disk.

Ideas:

• An array of objects works nicely if you read ahead, although this isn't required, see my code below (sorry about the indenting).

Here's a sample menu:

=========================== 1) Add an item to memory 2) Search memory for an item 3) List what's in memory 4) Total value on hand 5) Save to a file 6) Read in from a file

0) Exit Program 56 items stored

 #include  #include  #include  

 using namespace std; 

 class invItem { public: string name; string number; double price; int quantity; }; 

 void printItem(invItem someitem); 

 int main() { /// read in one record string itemName; string itemNumber; double itemPrice; int itemQuantity; 

 /// read in a single record from a file string inputBuffer; ifstream invFile("invent1.txt"); /// declares and opens 

 /// read and convert an item. 

 getline(invFile, itemName); getline(invFile, itemNumber); getline(invFile, inputBuffer); itemPrice = atof(inputBuffer.c_str()); getline(invFile, inputBuffer); itemQuantity = atoi(inputBuffer.c_str()); 

 To read the whole file use a loop that works like:  while (!eof) { read 4 lines into strings if (!eof) { convert and store the elements into the array } } 

 cout << "Item = " << itemName << "[" << itemNumber <<"]" << endl; cout << "Quantity = " << itemQuantity << " @ " << itemPrice << " = " << itemPrice * itemQuantity; invFile.close(); 

 /// write a single record to a file ofstream invOutFile("invent1.txt", ios::app); /// declare and open for append invOutFile << "White Sox" << endl; invOutFile << "82452374293742" << endl; invOutFile << 6.99 << endl; invOutFile << 20 << endl; invOutFile.close(); 

 /// build a single invItem object invItem someitem; someitem.name="Green Socks"; someitem.number="5435234523452345"; someitem.price=5.99; someitem.quantity=67; printItem(someitem); 

 /// build an array of invItem objects and save one to disk invItem items[1000]; items[0].name="Yellow Socks"; items[0].number="25435567456723452345"; items[0].price=7.99; items[0].quantity=27; printItem(items[0]); ofstream invOutFile2("invent1.txt", ios::app); /// declare and open for append invOutFile2 << items[0].name << endl; invOutFile2 << items[0].number << endl; invOutFile2 << items[0].price << endl; invOutFile2 << items[0].quantity<< endl; invOutFile2.close(); 

 return 0; } 

 void printItem(invItem someitem) { cout << "Item = " << someitem.name << "[" << someitem.number <<"]" << endl; cout << "Quantity = " << someitem.quantity << " @ " << someitem.price << " = " << someitem.price * someitem.quantity << endl; 

}