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Writing into a Binary File

closed account (9GEqko23)
Hello.
I seem to encounter a problem where I can't write the struct into my binary file for my program. It writes into the struct fine but when I close the program and open the binary file and output the data, it outputs nothing.

main (Basically just the menu)
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int main()
{
	Hardware records[100];	

	int count = 0;
	int input;
	bool truth = false;
	fstream file;

	int fileInput = fileOpen(file, records, count);

	if(fileInput == 1) //If a new file was made
	{
		newInput(file, records, count);
	}

	else //If there is an existing file
		cout << "Existing File" << endl;
	do {
		cout << "1. List all tools." << endl;
		cout << "2. Update a record." << endl;
		cout << "3. Insert a record." << endl;
		cout << "4. Delete a record." << endl;
		cout << "5. End Program." << endl;
		cout << "? ";
		cin >> input;

		if(input == 1)
		{
			cout << input << endl;
			output(file, records, count);
			truth = false;
		}

		else if(input == 2)
		{
			cout << input << endl;
			truth = false;
		}

		else if(input == 3)
		{
			cout << input << endl;
			truth = false;
		}

		else if(input == 4)
		{
			cout << input << endl;
			truth = false;
		}

		else if(input == 5)
		{
			cout << input << endl;
			truth = true;
		}

		else
			truth = true;
	} while(truth == false);

	file.close();
	
	return 0;
}


Header File
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#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <string>

using namespace std;

struct Hardware
{
	int num;
	char name[30];
	int quantity;
	double price;
};

int fileOpen(fstream& file, Hardware records[], int& count);

void newInput(fstream& file, Hardware records[], int& count);

void output(fstream& file, Hardware records[], int count);


My file with all of the functions, I think the problem lies within here:
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#include "hardware.h"

using namespace std;

int fileOpen(fstream& file, Hardware records[], int& count)
{
	file.open("hardware.dat");
	char input;
	bool truth = false;

	if(file.fail())
	{
		cout << "File cannot be opened. Create a new empty file" << endl;
		file.open("hardware.dat", ios::out);
		file.open("hardware.dat", ios::in | ios::out | ios::binary);

		file.clear();
		file.seekg(0, file.beg);

		for (int i = 0; i < 100; i++) //Writes into the binary file, making it empty
			file.write(reinterpret_cast<char *>(&records[i]), sizeof(Hardware));

		return 1; //If a new file is made
	}

	else if(file.good())
	{
		do {	cout << "Should the file be initialised (Y or N): ";
			cin >> input;
			if (input == 'Y' || input == 'y') //Clears Binary File
			{
				file.open("hardware.dat", ios::out);
				file.open("hardware.dat", ios::in | ios::out | ios::binary);

				file.clear();
				file.seekg(0, file.beg);

				for (int i = 0; i < 100; i++)
			file.write(reinterpret_cast<char *>(&records[i]), sizeof(Hardware));
				cout << "Yes" << endl;
				truth = true;
			}

			else if (input == 'N' || input == 'n') //Reads from existing binary file
			{
				for (int i = 0; i < 100; i++)
				{
				file.read(reinterpret_cast<char *>(&records[i]), sizeof(Hardware));
					if (records[i].num > 0)
						count++;
				}
				cout << "No" << endl;

				truth = true;
			}

			else
			{
				cout << "Invalid Input" << endl;
				truth = false;
			}
		} while(truth == false);
	return 2; //If there is an existing file
	}
}

void newInput(fstream& file, Hardware records[], int& count)
{
	//At the beginning of every function, read from the binary file
	for (int i = 0; i < 100; i++)
	{
	file.read(reinterpret_cast<char *>(&records[i]), sizeof(Hardware));
	}

	int numLoop = 0;	

	for (int i = 0; i < 100; i++)
	{
	bool truth = false;

	cout << "Enter the part number (0-99, -1 to end the input): ";
	do {
		cin >> numLoop;
	
		if(numLoop > 99)
		{
			cout << "Invalid Input. Try Again" << endl;
			truth = false;
		}

		else
		{
			truth = true;
		}
	} while(truth == false);

	if (numLoop < 0)
		break;

	else
		records[i].num = numLoop;

	cin.ignore();

	cout << "Enter the tool name: ";
	cin.get(records[i].name, 30, '\n');

	cin.ignore();

	cout << "Enter the quantity: ";
	cin >> records[i].quantity;
	
	cin.ignore();

	cout << "Enter the price: ";
	cin >> records[i].price;

	count++;
	}

	for (int i = 0; i < count; i++)
		file.write(reinterpret_cast<char *>(&records[i]), sizeof(Hardware));
}

void output(fstream& file, Hardware records[], int count)
{
	for (int i = 0; i < count; i++)
	file.read(reinterpret_cast<char *>(&records[i]), sizeof(Hardware));
	file.clear();
	file.seekg(0, file.beg);
	int location = file.tellg();
	cout << "Current Location: " << location << endl; 
	for (int i = 0; i < count; i++)
	{
	cout << count << '\t' << records[i].num << '\t' << records[i].name << '\t';
	cout << records[i].quantity << '\t' << records[i].price << endl;
	}
}
MiiNiPaa (8886)
Please, do not double post. It clutters forums and spreads attempts to help you. Another thread: http://www.cplusplus.com/forum/beginner/172928/
Topic archived. No new replies allowed.