The members functions of every object have access to a sort of magic pointer named 
this, which points to the object itself.  Thus any member function can find out the
address of the object of which it is a member.  

Example:
 // demonstration of this key word 
 # include<iostream.h>
  class sample
  {
   private: 
    char chararra[10];
   public:
    void reveal( )
     cout<<"my object's address is "<< this; 
};
  void main( )
  { 
   sample s1,s2,s3;
   s1.reveal( );
   s2.reveal( ); 
s3.reveal( );
} 

} 
The main( ) program in this example creates three objects of type sample, then asks each object to 
print its address, using the reveal( ) member function. This function prints out the value of the 
this pointer. 
 
Out put is 
 
 my object's address is 0x8f5effec 
  my object's address is ox8f5effec 
my object's address is ox8f5effec

Accessing Member data with this  

When you call a member function, it comes into existence with the value of this set of the address of the object for which it was called.  The this pointer can be treated like any other pointer to an object and can thus be used to access the data in the object to points.


// demonstration of accessing member function using this keyword 
# include<iostream.h>
class example
{
 private:
  int value;
 public:
  inline void display( );
  {
   this-> value = 35;
   cout<<"contents of the value =" <<this->value;
   cout<<endl;
}
void main( )
{
 example obj1;
 obj1.display( );
}
the output is
 contents of the value = 20