Reading and Writing Strings From a Binary File

binary_files.cpp

// ExploringFiles.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include <filesystem>
#include <fstream>
#include <vector>
#include <string>


void writeString(std::string string, std::ofstream& out) {
	size_t lengthOfString = string.length();
	out.write(reinterpret_cast<char*>(&lengthOfString), sizeof(size_t));
	out.write(string.c_str(), sizeof(char) * lengthOfString);
}

std::string readString(std::ifstream& in) {
	size_t lengthOfString;
	std::string string;

	in.read(reinterpret_cast<char*>(&lengthOfString), sizeof(size_t));

	string.resize(lengthOfString);

	in.read(&string[0], sizeof(char) * lengthOfString);

	return string;
}

int main() {
	std::ofstream outputFile{"data.bin", std::ios_base::binary};

	std::string outputString{"This is a test string."};
	writeString(outputString, outputFile);

	std::getline(std::cin, outputString);
	writeString(outputString, outputFile);

	outputFile.close();

	std::ifstream inputFile{"data.bin", std::ios_base::binary};
	std::cout << "First String: " << readString(inputFile) << "\n";
	std::cout << "Second String: " << readString(inputFile) << "\n";
}