Using cin >> and cout << to populate fields

I have a class in MyClass.h defined like this:

#ifndef MyClass_h
#define MyClass_h

#include <iostream>
#include <stdio.h>
#include <string>

using namespace std;

class MyClass {
public:
    string input
    void ReadFrom(istream &is);
    void WriteTo(ostream &os) const;
};
#endif /* MyClass_h */

MyClass.cpp looks like this:

#include <stdio.h>
#include <string>
#include <iostream>
#include "MyClass.h"

using namespace std;

void MyClass::ReadFrom(istream &is) {
    // put data into member 'input'
}

void MyClass::WriteTo(ostream &os) const {
    // output data in member 'input'
}

istream& operator >>(istream &is, MyClass &cls) {
    cls.ReadFrom(is);
    return is;
}

ostream& operator <<(ostream &os, const MyClass &cls) {
    cls.WriteTo(os);
    return os;
}

main.cpp looks like this:

#include <stdio.h>
#include <string>
#include <iostream>
#include "MyClass.h"

using namespace std;

int main(int argc, const char * argv[]) {
   MyClass c;
   std::cout << "Enter some input" << endl;
   std::cin >> c;
   return 0;
}

What I am trying to accomplish is to override the >> and << operators so that std::cin can simply read data into the class member(s), and then std::cout can spit out all of the data in those members.

I do not want to use friend functions.

Right now, I am getting an error around the std::cin >> c; line that says:

Invalid operands to binary expression ('istream' (aka 'basic_istream<char>') and 'MyClass')

The compiler fails to see the operator overloads in your main.cpp translation unit, because the overloads are not found in that file, nor are they found in any of the #include files. You need to declare both overloads in your MyClass.h file instead, after the MyClass declaration:

MyClass.h:

#ifndef MyClass_h
#define MyClass_h

#include <iostream>
#include <stdio.h>
#include <string>

using namespace std;

class MyClass {
public:
    string input
    void ReadFrom(istream &is);
    void WriteTo(ostream &os) const;
};

istream& operator >>(istream &is, MyClass &cls);    
ostream& operator <<(ostream &os, const MyClass &cls);

#endif /* MyClass_h */

You can leave the definitions as-is in your MyClass.cpp file.