File I/O

Reading and Writing from/to a file

main.cpp

// Project 09-02 
// Name:DynamicFileRectangle

#include <iostream>
#include <vector>
#include <fstream>
#include "Rectangle.h"
using namespace std;

void populateVector(vector<Rectangle*> &rec, ifstream& inputFile);
void outputToFile(vector<Rectangle*> &rectangles, ofstream& outputFile);
void clearVector(vector<Rectangle*> &rectangles);

int main()
{
	cout << "Opening rectangles.txt";

	ifstream inputFile;
	ofstream outputFile;
	inputFile.open("rectangles.txt");
	outputFile.open("output.txt");

	if (!inputFile) {
		cerr << "Error opening file, grabbing parachute and jumping out";
		return 1;
	}

	cout << "Processing data..." << endl;

	vector<Rectangle*> Rectangles;
    
	populateVector(Rectangles, inputFile);
	outputToFile(Rectangles, outputFile);
	clearVector(Rectangles);

	cout << "Done!" << endl;
    
    inputFile.close();
    outputFile.close();

    return 0;
}

void populateVector(vector<Rectangle*> &rec, ifstream& inputFile)
{
    Rectangle* temp;
    int length;
    int width;
	while (!inputFile.eof()) {
		inputFile >> length >> width;

		temp =  new Rectangle (length, width);
		rec.push_back(temp);
	}
}

void outputToFile(vector<Rectangle*> &rectangles, ofstream& outputFile)
{
	for (Rectangle* rectangle : rectangles) {
		outputFile << "Area: " << rectangle->area() << " " << '\t' << rectangle->perimeter() << endl;
	}
}

void clearVector(vector<Rectangle *>& rectangles)
{
	for (Rectangle *rectangle : rectangles) {
		delete rectangle;
		rectangle = nullptr;    // not required since rectangles.clear() will be called
	}
	rectangles.clear();
}

Rectangle.h

#ifndef RECTANGLE_H
#define RECTANGLE_H

class Rectangle
{
	public:
		Rectangle();
		Rectangle(double length, double width);
		double getLength() const;
		double getWidth() const;
		void setLength(double length);
		void setWidth(double width);
		double area() const;
		double perimeter() const;

	private:
		double length;
		double width;
};

#endif

Rectangle.cpp

#include "Rectangle.h"

Rectangle::Rectangle()
{
	this->length = 1.0;
	this->width = 1.0;
}

Rectangle::Rectangle(double length, double width)
{
	this->length = length;
	this->width = width;
}

double Rectangle::getLength() const
{
	return length;
}
double Rectangle::getWidth() const
{
	return width;
}

void Rectangle::setLength(double length)
{
	this->length = length;
}

void Rectangle::setWidth(double width)
{
	this->width = width;
}

double Rectangle::area() const
{
	return length * width;
}

double Rectangle::perimeter() const
{
	return 2 * length + 2 * width;  
}