Запись объектов в файл и чтение

#include <fstream.h>
#include <iostream.h>
#include <conio.h>
#include <string.h>
 
class my {
int a;
float b;
char c[30];
 
public:
void create()    

{ cout<<"Input a = "; cin>>a; cin.ignore();
cout<<"input b = "; cin>>b; cin.ignore();
cout<<"Input c = "; cin.getline(c,30);
cout<<this<<" created";
}
void show()
{cout<<"a = "<<a<<endl<<"b = "<<b<<endl<<"c = "<<c; getch();}
 
};
 
void main()
{ clrscr();
my obj,obj1;
ofstream  myclass("myfile.txt",ios::binary);
do { cout<<"1. Create obj\n2. Save obj\n3. Open obg\n4. Show obj\n";
switch(getche()) {
            case '1': {obj.create();} break;
         case '2': {myclass.write(reinterpret_cast<char*>(&obj),sizeof(obj));} break;
         case '3': {ifstream my("myfile.txt",ios::binary);  my.read(reinterpret_cast<char*>(&obj1),sizeof(obj1));} break;
         case '4': {obj1.show();} break;
}
}while(255);
getch();
}

#include <iostream>
#include <fstream>
 
class my {
    int a;
    float b;
    char c[30];
    public:
    friend std::ostream& operator<<(std::ostream& o, my& x){
        std::cout<<"a= "<<x.a<<", b= "<<x.b<<", c= "<<x.c;
    }
    void create(){
        std::cout<<"a = "; std::cin>>a;
        std::cout<<"b = "; std::cin>>b; std::cin.ignore();
        std::cout<<"c = "; std::cin.getline(c, 30);
        std::cout<<*this<<" created\n";
    }
};
 
int main (){
    my o, o1;
    o.create();
    std::ofstream ofs("text.txt", std::ios::binary);
    ofs.write(reinterpret_cast<char*>(&o), sizeof(o));
    ofs.close();
    std::ifstream ifs("text.txt", std::ios::binary);
    if(!ifs){std::cerr<<"File not found"; return 1;}
    ifs.read(reinterpret_cast<char*>(&o1), sizeof(o1));
    ifs.close();
    std::cout<<"o1: "<<o1<<"\n";
}

#include <iostream>
#include <fstream>
 
class my {
    int a;
    float b;
    char c[30];
public:
    friend std::ostream& operator<<(std::ostream& o, my& x) {
        std::cout << "a= " << x.a << ", b= " << x.b << ", c= " << x.c;
        return o;
    }
    void create() {
        std::cout << "a = "; std::cin >> a;
        std::cout << "b = "; std::cin >> b; std::cin.ignore();
        std::cout << "c = "; std::cin.getline(c, 30);
        std::cout << *this << " created\n";
    }
};
 
int main() {
    my o, o1;
    o.create();
    std::ofstream ofs("text.txt", std::ios::binary);
    ofs.write(reinterpret_cast<char*>(&o), sizeof(o));
    ofs.close();
    std::ifstream ifs("text.txt", std::ios::binary);
    if (!ifs) { std::cerr << "File not found"; return 1; }
    ifs.read(reinterpret_cast<char*>(&o1), sizeof(o1));
    ifs.close();
    std::cout << "o1: " << o1 << "\n";
}