Object class
C# defines one special class called object that is an implicit base class of all other classes and for all other types. object is a base class for all other types and that boxing of the value types takes place automatically, it is possible to use object as a “universal” data type.

Object class methods

Method	Purpose
public virtual bool Equals(object ob)	Determines whether the invoking object is the same as the one referred to by ob.
public static bool Equals(object ob1, object ob2)	Determines whether ob1 is the same as ob2.
protected Finalize( )	Performs shutdown actions prior to garbage collection. In C#, Finalize( ) is accessed through a destructor.
public virtual int GetHashCode( )	Returns the hash code associated with the invoking object.
public Type GetType( )	Obtains the type of an object at runtime.
protected object MemberwiseClone( )	Makes a “shallow copy” of the object. (The members are copied, but objects referred to by members are not.)
public static bool ReferenceEquals(object ob1, object ob2)	Determines whether ob1 and ob2 refer to the same object.
public virtual string ToString( )	Returns a string that describes the object

 

           
Boxing and Unboxing
object is a base class for all other types and that boxing of the value types takes place automatically, it is possible to use object as a “universal” data type.
When an object reference refers to a value type, a process known as boxing occurs. Boxing causes the value of a value type to be stored in an object instance. Thus, a value type is “boxed” inside an object. This object can then be used like any other object. In all cases, boxing occurs automatically. You simply assign a value to an object reference.
Unboxing is the process of retrieving a value from a boxed object. This action is performed using an explicit cast from the object reference to its corresponding value type. Attempting to unbox an object into a different type will result in a runtime error.
Program on boxing
using System;
class Sample
{
public static void Main(String[] args)
{
int a = 10;
object x;
x = a; // boxing
int k =(int) x;//unboxing
Console.WriteLine("Value of k after unboxing" + k);

 

    }
}
Program to find the factorial values using boxing and unboxing
using System;
class Sample
{
public static void Main(String[] args)
{
int a;
Console.WriteLine("Enter no");
a =Convert.ToInt32 ( Console.ReadLine());
Console.WriteLine("Factorial" + fact(a));
}
public static int fact(object x)
{
int f = 1;
for (int i = 1; i <= (int)x; i++)
{
f = f * i;
}
return f;
}
}