Serialization - Object Serialization

Object Serialization
Introduction
The C++ language provides a somewhat limited support for file processing. This is probably based on the time it was conceived and put to use. Many languages that were developed after C++, such as (Object) Pascal and Java provide a better support, probably because their libraries were implemented as the demand was made obvious. Based on this, C++ supports saving only values of primitive types such as short, int, char double. This can be done by using either the C FILE structure or C++' own fstream class.

Binary Serialization
Object serialization consists of saving the values that are part of an object, mostly the value gotten from declaring a variable of a class. AT the current standard, C++ doesn't inherently support object serialization. To perform this type of operation, you can use a technique known as binary serialization.
When you decide to save a value to a medium, the fstream class provides the option to save the value in binary format. This consists of saving each byte to the medium by aligning bytes in a contiguous manner, the same way the variables are stored in binary numbers.
To indicate that you want to save a value as binary, when declaring the ofstream variable, specify the ios option as binary. Here is an example:
#include <fstream>
#include <iostream>
using namespace std;

class Student
{
public:
 char   FullName[40];
 char   CompleteAddress[120];
 char   Gender;
 double Age;
 bool   LivesInASingleParentHome;
};
int main()
{
 Student one;
 strcpy(one.FullName, "Ernestine Waller");
 strcpy(one.CompleteAddress, "824 Larson Drv, Silver Spring, MD 20910");
 one.Gender = 'F';
 one.Age = 16.50;
 one.LivesInASingleParentHome = true;

 ofstream ofs("fifthgrade.ros", ios::binary);

 return 0;
}
Writing to the Stream
The ios::binary option lets the compiler know how the value will be stored. This declaration also initiates the file. To write the values to a stream, you can call the fstream::write()method.
After calling the write() method, you can write the value of the variable to the medium. Here is an example:
#include <fstream>
#include <iostream>

using namespace std;

class Student
{
public:
 char   FullName[40];
 char   CompleteAddress[120];
 char   Gender;
 double Age;
 bool   LivesInASingleParentHome;
};
int main()
{
 Student one;
 strcpy(one.FullName, "Ernestine Waller");
 strcpy(one.CompleteAddress, "824 Larson Drv, Silver Spring, MD 20910");
 one.Gender = 'F';
 one.Age = 16.50;
 one.LivesInASingleParentHome = true;
 ofstream ofs("fifthgrade.ros", ios::binary);

 ofs.write((char *)&one, sizeof(one));

 return 0;
}

Reading From the Stream
Reading an object saved in binary format is as easy as writing it. To read the value, call the ifstream::read() method. Here is an example:
#include <fstream>
#include <iostream>

using namespace std;

class Student
{
public:
 char   FullName[40];
 char   CompleteAddress[120];
 char   Gender;
 double Age;
 bool   LivesInASingleParentHome;
};
int main()
{
/* Student one;
 strcpy(one.FullName, "Ernestine Waller");
 strcpy(one.CompleteAddress, "824 Larson Drv, Silver Spring, MD 20910");
 one.Gender = 'F';
 one.Age = 16.50;
 one.LivesInASingleParentHome = true;
 ofstream ofs("fifthgrade.ros", ios::binary);

 ofs.write((char *)&one, sizeof(one));

*/ Student two;

 ifstream ifs("fifthgrade.ros", ios::binary);

 ifs.read((char *)&two, sizeof(two));

 cout << "Student Information\n";
 cout << "Student Name: " << two.FullName << endl;
 cout << "Address:      " << two.CompleteAddress << endl;
 if( two.Gender == 'f' || two.Gender == 'F' )
  cout << "Gender:       Female" << endl;
 else if( two.Gender == 'm' || two.Gender == 'M' )
  cout << "Gender:       Male" << endl;
 else
  cout << "Gender:       Unknown" << endl;

 cout << "Age:          " << two.Age << endl;
 if( two.LivesInASingleParentHome == true )
  cout << "Lives in a single parent home" << endl;
 else
  cout << "Doesn't live in a single parent home" << endl;
 cout << "\n";
 return 0;

}


Serialization with Boost Library :




http://www.boost.org/doc/libs/1_63_0/libs/serialization/doc/tutorial.html












































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