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external data file

lazyman (20)
Below is my code, its a running code however its not writing the user input to the EXTERNAL DATA FILE. Please help



// Name: Class:
// Purpose of the program...
// is to manage an array of apps
// providing a way to read and display
// using structures and functions

#include <iostream>
#include <fstream>
using namespace std;
#include <cstring>
#include <cctype>

//Create constants used as array sizes
const int SIZE_TITLE = 131;
const int SIZE_DESC = 300;
const int SIZE_PAGE = 6;


//This creates a grouping for an individual app
struct app
{
char name[SIZE_TITLE];
char description[SIZE_DESC];
char page[SIZE_PAGE];
int length;
};

void displayall(app &); //display all members
void getfilename(char filename[]); //function for getting the external data file
void readall(app &); //reads the input
bool save_app(char filename[], app[], int num);
bool load_app(char filename[], app[], int & num);
bool more();


int main ()
{
app user[20]; //collection of apps for the user
char filename[40]; //holds the file name
int num_apps=0; //number of apps in the array
char rerun;
int max_num_apps = 200;


getfilename(filename);
if(!load_app(filename, user, num_apps));
cout<<"we are starting from stratch!"<<endl<<endl;


int i = num_apps;
do
{
readall(user[i]);
displayall(user[i]);

}while(more() && i < max_num_apps);

save_app(filename, user, i);
cout<<"please try agian";

//display everything
cout<<"The entire file contains these apps: ";
for (int j = 0; j < i; ++j)
displayall(user[j]);






return 0;
}



//Ask the user what file they want to work with
void getfilename(char array[])
{
cout<<"Please enter the name of a file limited to 31 characters: ";
cin.get(array,35,'\n');
cin.ignore(100,'\n');
strcat(array,".txt");

}

//read in all the users apps
void readall(app & an_app)
{
cout<<"Please enter the title: ";
cin.get(an_app.name,131,'\n');
cin.ignore(131,'\n');
}

//write all of the movies OUT to a file
bool save_app(char filename[], app apps[], int num)
{
bool success = true;
ofstream write;
write.open(filename);
write <<"this is a test1.";
if (!write)
{
cout <<"Can't save, try agian \n\n";
success = false;
}
else
{
for(int i=0; i < num; ++i)
{
write <<"this is a test.";
write <<apps[i].name <<"|" <<endl;
}
write.close();
write.clear();
}
return success;
}

//load all movies FROM an external file
bool load_app(char filename[], app apps[], int & num)
{
ifstream read;
read.open(filename);

if(!read)
return false;

read.get(apps[num].name,131,'|');
read.ignore(131,'|');
read.close();
return true;
}



//later be used for a loop
bool more()
{
char response;
cout <<"Would you like to enter another? Y/N ";
cin >>response;
cin.ignore(100,'\n');
if (toupper(response) == 'Y')
return true;
return false;
}

void displayall(app & program)
{
cout << "\n\n" <<program.name<<'\t'<<endl;
}
MikeyBoy (5631)
Please could you enclose your code in code tags, to make it easier to read?

You can get code tags using the "<>" button to the right of the edit window.
toum (353)
It's because you call save_app() with i equal to 0.
In your main, a "++i;" is missing at the end of your do/while loop.
lazyman (20)
When it askes me if i want to enter more data and I enter N it just closes out the program instead of displaying all of the data. Any Ideas?
lazyman (20)
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// Name:   Class:  
// Purpose of the program...
// is to manage an array of apps 
// providing a way to read and display
// using structures and functions

#include <iostream>
#include <fstream>
using namespace std;
#include <cstring>
#include <cctype>

//Create constants used as array sizes
const int SIZE_TITLE = 131;
const int SIZE_DESC = 300;
const int SIZE_PAGE = 6;


//This creates a grouping for an individual app
struct app
{
    char name[SIZE_TITLE];
    char description[SIZE_DESC];
    char page[SIZE_PAGE];
};

void displayall(app &); //display all members
void getfilename(char filename[]); //function for getting the external data file
void readall(app &);  //reads the input
bool save_app(char filename[], app[], int num); 
bool load_app(char filename[], app[], int & num);
bool more();


int main ()
{
    app user[20]; //collection of apps for the user
    char filename[40]; //holds the file name 
    int num_apps=0; //number of apps in the array
    char rerun;
    int max_num_apps = 200;
    

    getfilename(filename);
    if(!load_app(filename, user, num_apps))
                           cout<<"No file found, starting from scratch\n";
    cout<<endl<<endl;                     
    
    
    int i = num_apps; 
    do 
    {
    readall(user[i]);
    displayall(user[i]);
    ++i;
    }while (more() && i < max_num_apps);

     save_app(filename, user, i);
 
       
    //display everything
    cout<<"The entire file contains these apps: ";
    for (int j = 0; j < i; ++j)
        displayall(user[j]);   
    


    
    

    return 0;
}



//Ask the user what file they want to work with
void getfilename(char array[])
{
    cout<<"Please enter the name of a file limited to 31 characters: ";
    cin.get(array,35,'\n');
    cin.ignore(100,'\n');
    strcat(array,".txt");
 
}

//read in all the users apps
void readall(app & an_app)
{
     cout<<"Please enter the title: ";
     cin.get(an_app.name,131,'\n');
     cin.ignore(131,'\n');
     cout<<"Please enter the description: ";
     cin.get(an_app.description,300,'\n');
     cin.ignore(301,'\n');
     cout<<"Please enter what page the app is on: ";
     cin.get(an_app.page,6,'\n');
     cin.ignore(7,'\n');
}

//write all of the movies OUT to a file
bool save_app(char filename[], app apps[], int num)
{
     bool success = true;
     ofstream write;
     write.open(filename);
     if (!write)
     {
                cout <<"Can't save, try agian \n\n";
                success = false;
                }
     else
     {
         for(int i=0; i < num; ++i)
         {
                 
                 write <<apps[i].name <<"|";
                 write <<apps[i].description <<"|";
                 write <<apps[i].page <<endl;
                 }
     write.close();
     write.clear();
     }
     return success;
}

//load all movies FROM an external file
bool load_app(char filename[], app apps[], int & num)
{
     ifstream read;
     read.open(filename);
     
     if(!read)
     return false;
     
     
     
     read.get(apps[num].name,131,'|');
     read.ignore(131,'|');
     while(read && !read.eof())
     {
     read.get(apps[num].description,300,'|');
     read.ignore(300,'|');
     read.get(apps[num].page,6,'|');
     read.ignore(6,'|');
     ++num;
     read.get(apps[num].name,131,'|');
     read.ignore(131,'|');
     }
     read.close();
     return true;
}
     
     

//later be used for a loop
bool more()
{
    char response;
    cout <<"Would you like to enter another? Y/N ";
    cin >>response;
    cin.ignore(10,'\n');
    if (toupper(response) == 'Y')
       return true;
    return false;
}

void displayall(app & program)
{
     cout << "\nApp name: " <<program.name<<'\t'<<endl;
     cout << "\nDescription of program: " <<program.description<<'\t'<<endl;
     cout << "\nPage: " <<program.page<<'\t'<<endl;
     
}
toum (353)
How are you executing your program ?
By double-clicking on the .exe file or by calling it from the console ?
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