public static System.Void Enter(System.Object obj)

Acquires an exclusive lock on the specified object.

Parameter obj: The System.Object on which to acquire the lock.

Throws: : obj is null.

This method acquires an exclusive lock on obj . A caller of this method is required to invoke System.Threading.Monitor.Exit(System.Object) once for each System.Threading.Monitor.Enter(System.Object) invoked. The caller of this method is blocked if another thread has obtained the lock by calling System.Threading.Monitor.Enter(System.Object) and specifying the same object. The caller is not blocked if the current thread holds the lock. The same thread can invoke System.Threading.Monitor.Enter(System.Object) more than once (and it will not block); however, an equal number of System.Threading.Monitor.Exit(System.Object) calls are required to be invoked before other threads waiting on the object will unblock. Invoking this member is identical to using the C# lock statement.

public static System.Void Exit(System.Object obj)

Releases an exclusive lock on the specified System.Object .

Parameter obj: The System.Object on which to release the lock.

Throws: : obj is null.

Throws: : The current thread does not own the lock for the specified object.

This method releases an exclusive lock on obj. The caller is required to own the lock on obj . If the caller owns the lock on the specified object, and has made an equal number of System.Threading.Monitor.Exit(System.Object) and System.Threading.Monitor.Enter(System.Object) calls for the object, then the lock is released. If the caller has not invoked System.Threading.Monitor.Exit(System.Object) as many times as System.Threading.Monitor.Enter(System.Object) , the lock is not released. If the lock is released and there are other threads in the ready queue for the object, one of the threads will acquire the lock. If there are other threads in the waiting queue waiting to acquire the lock, they are not automatically moved to the ready queue when the owner of the lock calls System.Threading.Monitor.Exit(System.Object). To move one or more waiting threads into the ready queue, call System.Threading.Monitor.Pulse(System.Object) or System.Threading.Monitor.PulseAll(System.Object) prior to invoking System.Threading.Monitor.Exit(System.Object).

public static System.Void Pulse(System.Object obj)

Notifies the next waiting thread (if any) of a change in the specified locked object's state.

Parameter obj: The System.Object a thread may be waiting for.

Throws: : obj is null.

Throws: : The calling thread does not own the lock for the specified object.

The thread that currently owns the lock on the specified object invokes this method to signal the next thread in line for the lock (in the queue of threads waiting to acquire the lock on the object). Upon receiving the pulse, the waiting thread is moved to the ready queue. When the thread that invoked Pulse releases the lock, the next thread in the ready queue (which is not necessarily the thread that was pulsed) acquires the lock. To signal a waiting object using Pulse , you must be the current owner of the lock. To signal multiple threads, use the System.Threading.Monitor.PulseAll(System.Object) method.

public static System.Void PulseAll(System.Object obj)

Notifies all waiting threads (if any) of a change in the specified locked object's state.

Parameter obj: The System.Object that one or more threads may be waiting for.

Throws: : obj is null.

Throws: : The calling thread does not own the lock for the specified object.

The thread that currently owns the lock on the specified object invokes this method to signal all threads waiting to acquire the lock on the object. After the signal is sent, the waiting threads are moved to the ready queue. When the thread that invoked PulseAll releases the lock, the next thread in the ready queue acquires the lock. To signal waiting objects using PulseAll, you must be the current owner of the lock. To signal a single thread, use the System.Threading.Monitor.Pulse(System.Object) method.

public static System.Boolean TryEnter(System.Object obj)

Attempts to acquire an exclusive lock on the specified object.

Parameter obj: The System.Object on which to acquire the lock.

Returns: true if the current thread acquired the lock; otherwise, false.

Throws: : obj is null.

If successful, this method acquires an exclusive lock on obj. This method returns immediately, whether or not the lock is available. This method is equivalent to System.Threading.Monitor.TryEnter(System.Object) (obj, 0).

public static System.Boolean TryEnter(System.Object obj, System.Int32 millisecondsTimeout)

Attempts, for the specified number of milliseconds, to acquire an exclusive lock on the specified object.

Parameter obj: The System.Object on which to acquire the lock.

Parameter millisecondsTimeout: A System.Int32 containing the maximum number of milliseconds to wait for the lock.

Returns: true if the current thread acquired the lock; otherwise, false.

Throws: : obj is null.

Throws: : millisecondsTimeout is negative, and not equal to System.Threading.Timeout.Infinite .

If successful, this method acquires an exclusive lock on obj. If millisecondsTimeout equals System.Threading.Timeout.Infinite, this method is equivalent to System.Threading.Monitor.Enter(System.Object) (obj). If millisecondsTimeout equals zero, this method is equivalent to System.Threading.Monitor.TryEnter(System.Object) (obj).

public static System.Boolean TryEnter(System.Object obj, System.TimeSpan timeout)

Attempts, for the specified amount of time, to acquire an exclusive lock on the specified object.

Parameter obj: The System.Object on which to acquire the lock.

Parameter timeout: A System.TimeSpan set to the maximum amount of time to wait for the lock.

Returns: true if the current thread acquires the lock; otherwise, false.

Throws: : obj is null.

Throws: : The value of timeout in milliseconds is negative and is not equal to System.Threading.Timeout.Infinite , or is greater than System.Int32.MaxValue .

If successful, this method acquires an exclusive lock on obj. If the value of timeout converted to milliseconds equals System.Threading.Timeout.Infinite, this method is equivalent to System.Threading.Monitor.Enter(System.Object) (obj). If the value of timeout equals zero, this method is equivalent to System.Threading.Monitor.TryEnter(System.Object) (obj).

public static System.Boolean Wait(System.Object obj, System.Int32 millisecondsTimeout)

Releases the lock on an object and blocks the current thread until it reacquires the lock or until a specified amount of time elapses.

Parameter obj: The System.Object on which to wait.

Parameter millisecondsTimeout: A System.Int32 containing the maximum number of milliseconds to wait before this method returns.

Returns: true if the lock was reacquired before the specified time elapsed; otherwise, false.

Throws: : obj is null.

Throws: : The calling thread does not own the lock for the specified object.

Throws: : The value of millisecondsTimeout is negative, and not equal to System.Threading.Timeout.Infinite .

If successful, this method reacquires an exclusive lock on obj. This method behaves identically to System.Threading.Monitor.Wait(System.Object,System.Int32,System.Boolean) (obj), except that it does not block indefinitely unless System.Threading.Timeout.Infinite is specified for millisecondsTimeout . Once the specified time has elapsed, this method returns a value that indicates whether the lock has been reacquired by the caller. If millisecondsTimeout equals 0, this method returns immediately. This method is called when the caller is waiting for a change in the state of the object, which occurs as a result of another thread's operations on the object. For additional details, see System.Threading.Monitor.Wait(System.Object,System.Int32,System.Boolean) (obj).

public static System.Boolean Wait(System.Object obj, System.TimeSpan timeout)

Releases the lock on an object and blocks the current thread until it reacquires the lock or until a specified amount of time elapses.

Parameter obj: The System.Object on which to wait.

Parameter timeout: A System.TimeSpan set to the maximum amount of time to wait before this method returns.

Returns: true if the lock was reacquired before the specified time elapsed; otherwise, false.

Throws: : obj is null.

Throws: : The calling thread does not own the lock for the specified object.

Throws: : If timeout is negative, and is not equal to System.Threading.Timeout.Infinite , or is greater than System.Int32.MaxValue.

If successful, this method reacquires an exclusive lock on obj. This method behaves identically to System.Threading.Monitor.Wait(System.Object,System.Int32,System.Boolean) (obj), except that it does not block indefinitely unless System.Threading.Timeout.Infinite milliseconds is specified for timeout . Once the specified time has elapsed, this method returns a value that indicates whether the lock has been reacquired by the caller. If timeout equals 0, this method returns immediately. This method is called when the caller is waiting for a change in the state of the object, which occurs as a result of another thread's operations on the object. For additional details, see System.Threading.Monitor.Wait(System.Object,System.Int32,System.Boolean) (obj ).

public static System.Boolean Wait(System.Object obj)

Releases the lock on an object and blocks the current thread until it reacquires the lock.

Parameter obj: The System.Object on which to wait.

Returns: true if the call returned because the caller reacquired the lock for the specified object. This method does not return if the lock is not reacquired.

Throws: : obj is null.

Throws: : The calling thread does not own the lock for the specified object.

This method reacquires an exclusive lock on obj. The thread that currently owns the lock on the specified object invokes this method in order to release the object so that another thread can access it. The caller is blocked while waiting to reacquire the lock. This method is called when the caller is waiting for a change in the state of the object, which occurs as a result of another thread's operations on the object. When a thread calls Wait, it releases the lock on the object and enters the object's waiting queue. The next thread in the object's ready queue (if there is one) acquires the lock and has exclusive use of the object. All threads that call Wait remain in the waiting queue until they receive a signal via System.Threading.Monitor.Pulse(System.Object) or System.Threading.Monitor.PulseAll(System.Object) sent by the owner of the lock. If Pulse is sent, only the thread at the head of the waiting queue is affected. If PulseAll is sent, all threads that are waiting for the object are affected. When the signal is received, one or more threads leave the waiting queue and enter the ready queue. A thread in the ready queue is permitted to reacquire the lock. This method returns when the calling thread reacquires the lock on the object. Note that this method blocks indefinitely if the holder of the lock does not call System.Threading.Monitor.Pulse(System.Object) or System.Threading.Monitor.PulseAll(System.Object). The caller executes System.Threading.Monitor.Wait(System.Object,System.Int32,System.Boolean) once, regardless of the number of times System.Threading.Monitor.Enter(System.Object) has been invoked for the specified object. Conceptually, the System.Threading.Monitor.Wait(System.Object,System.Int32,System.Boolean) method stores the number of times the caller invoked System.Threading.Monitor.Enter(System.Object) on the object and invokes System.Threading.Monitor.Exit(System.Object) as many times as necessary to fully release the locked object. The caller then blocks while waiting to reacquire the object. When the caller reacquires the lock, the system calls System.Threading.Monitor.Enter(System.Object) as many times as necessary to restore the saved Enter count for the caller. Calling System.Threading.Monitor.Wait(System.Object,System.Int32,System.Boolean) releases the lock for the specified object only; if the caller is the owner of locks on other objects, these locks are not released.

public virtual System.Boolean Equals(System.Object obj)

Determines whether the specified System.Object is equal to the current instance.

Parameter obj: The System.Object to compare with the current instance.

Returns: true if obj is equal to the current instance; otherwise, false.

The statements listed below are required to be true for all implementations of the System.Object.Equals(System.Object) method. In the list, x, y, and z represent non-null object references. See System.Object.GetHashCode for additional required behaviors pertaining to the System.Object.Equals(System.Object) method. Implementations of System.Object.Equals(System.Object) should not throw exceptions. The System.Object.Equals(System.Object) method tests for referential equality , which means that System.Object.Equals(System.Object) returns true if the specified instance of Object and the current instance are the same instance; otherwise, it returns false . An implementation of the System.Object.Equals(System.Object) method is shown in the following C# code: public virtual bool Equals(Object obj) { return this == obj; } For some kinds of objects, it is desirable to have System.Object.Equals(System.Object) test for value equality instead of referential equality. Such implementations of Equals return true if the two objects have the same "value", even if they are not the same instance. The definition of what constitutes an object's "value" is up to the implementer of the type, but it is typically some or all of the data stored in the instance variables of the object. For example, the value of a System.String is based on the characters of the string; the Equals method of the System.String class returns true for any two string instances that contain exactly the same characters in the same order. When the Equals method of a base class provides value equality, an override of Equals in a class derived from that base class should invoke the inherited implementation of Equals . It is recommended (but not required) that types overriding System.Object.Equals(System.Object) also override System.Object.GetHashCode. Hashtables cannot be relied on to work correctly if this recommendation is not followed. If your programming language supports operator overloading, and if you choose to overload the equality operator for a given type, that type should override the Equals method. Such implementations of the Equals method should return the same results as the equality operator. Following this guideline will help ensure that class library code using Equals (such as System.Collections.ArrayList and System.Collections.Hashtable ) behaves in a manner that is consistent with the way the equality operator is used by application code. If you are implementing a value type, you should follow these guidelines: For reference types, the guidelines are as follows: If you implement System.IComparable on a given type, you should override Equals on that type. The System.Object.Equals(System.Object) method is called by methods in collections classes that perform search operations, including the System.Array.IndexOf(System.Array,System.Object) method and the System.Collections.ArrayList.Contains(System.Object) method.

using System;
class MyClass {
   static void Main() {
      Object obj1 = new Object();
      Object obj2 = new Object();
      Console.WriteLine(obj1.Equals(obj2));
      obj1 = obj2; 
      Console.WriteLine(obj1.Equals(obj2)); 
   }
}

using System;
public class Point: object {
 int x, y;
 public override bool Equals(Object obj) {
 //Check for null and compare run-time types.
 if (obj == null || GetType() != obj.GetType()) return false;
 Point p = (Point)obj;
 return (x == p.x) && (y == p.y);
 }
 public override int GetHashCode() {
 return x ^ y;
 }
}

class Point3D: Point {
 int z;
 public override bool Equals(Object obj) {
 return base.Equals(obj) && z == ((Point3D)obj).z;
 }
 public override int GetHashCode() {
 return base.GetHashCode() ^ z;
 }
}

using System;
class Rectangle {
 Point a, b;
 public override bool Equals(Object obj) {
 if (obj == null || GetType() != obj.GetType()) return false;
 Rectangle r = (Rectangle)obj;
 //Use Equals to compare instance variables
 return a.Equals(r.a) && b.Equals(r.b);
 }
 public override int GetHashCode() {
 return a.GetHashCode() ^ b.GetHashCode();
 }
}

using System;
public struct Complex {
 double re, im;
 public override bool Equals(Object obj) {
 return obj is Complex && this == (Complex)obj;
 }
 public override int GetHashCode() {
 return re.GetHashCode() ^ im.GetHashCode();
 }
 public static bool operator ==(Complex x, Complex y) {
 return x.re == y.re && x.im == y.im;
 }
 public static bool operator !=(Complex x, Complex y) {
 return !(x == y);
 }
}

public static System.Boolean Equals(System.Object objA, System.Object objB)

Determines whether two object references are equal.

Parameter objA: First object to compare.

Parameter objB: Second object to compare.

Returns: true if one or more of the following statements is true: otherwise returns false.

This static method checks for null references before it calls objA.Equals(objB ) and returns false if either objA or objB is null. If the Equals(object obj) implementation throws an exception, this method throws an exception.

using System;

public class MyClass {
   public static void Main() {
   string s1 = "Tom";
   string s2 = "Carol";
   Console.WriteLine("Object.Equals(\"{0}\", \"{1}\") => {2}", 
      s1, s2, Object.Equals(s1, s2));

   s1 = "Tom";
   s2 = "Tom";
   Console.WriteLine("Object.Equals(\"{0}\", \"{1}\") => {2}", 
      s1, s2, Object.Equals(s1, s2));

   s1 = null;
   s2 = "Tom";
   Console.WriteLine("Object.Equals(null, \"{1}\") => {2}",
       s1, s2, Object.Equals(s1, s2));

   s1 = "Carol";
   s2 = null;
   Console.WriteLine("Object.Equals(\"{0}\", null) => {2}", 
       s1, s2, Object.Equals(s1, s2));

   s1 = null;
   s2 = null;
   Console.WriteLine("Object.Equals(null, null) => {2}", 
       s1, s2, Object.Equals(s1, s2));
   }
}
   

public System.Void Finalize()

Allows a System.Object to perform cleanup operations before the memory allocated for the System.Object is automatically reclaimed.

During execution, System.Object.Finalize is automatically called after an object becomes inaccessible, unless the object has been exempted from finalization by a call to System.GC.SuppressFinalize(System.Object). During shutdown of an application domain, System.Object.Finalize is automatically called on objects that are not exempt from finalization, even those that are still accessible. System.Object.Finalize is automatically called only once on a given instance, unless the object is re-registered using a mechanism such as System.GC.ReRegisterForFinalize(System.Object) and System.GC.SuppressFinalize(System.Object) has not been subsequently called. Conforming implementations of the CLI are required to make every effort to ensure that for every object that has not been exempted from finalization, the System.Object.Finalize method is called after the object becomes inaccessible. However, there may be some circumstances under which Finalize is not called. Conforming CLI implementations are required to explicitly specify the conditions under which Finalize is not guaranteed to be called. For example, Finalize might not be guaranteed to be called in the event of equipment failure, power failure, or other catastrophic system failures. In addition to System.GC.ReRegisterForFinalize(System.Object) and System.GC.SuppressFinalize(System.Object), conforming implementations of the CLI are allowed to provide other mechanisms that affect the behavior of System.Object.Finalize . Any mechanisms provided are required to be specified by the CLI implementation. The order in which the Finalize methods of two objects are run is unspecified, even if one object refers to the other. The thread on which Finalize is run is unspecified. Every implementation of System.Object.Finalize in a derived type is required to call its base type's implementation of Finalize . This is the only case in which application code calls System.Object.Finalize . The System.Object.Finalize implementation does nothing. A type should implement Finalize when it uses unmanaged resources such as file handles or database connections that must be released when the managed object that uses them is reclaimed. Because Finalize methods may be invoked in any order (including from multiple threads), synchronization may be necessary if the Finalize method may interact with other objects, whether accessible or not. Furthermore, since the order in which Finalize is called is unspecified, implementers of Finalize (or of destructors implemented through overriding Finalize) must take care to correctly handle references to other objects, as their Finalize method may already have been invoked. In general, referenced objects should not be considered valid during finalization. See the System.IDisposable interface for an alternate means of disposing of resources. For C# developers: Destructors are the C# mechanism for performing cleanup operations. Destructors provide appropriate safeguards, such as automatically calling the base type's destructor. In C# code, System.Object.Finalize cannot be called or overridden.

public virtual System.Int32 GetHashCode()

Generates a hash code for the current instance.

Returns: A System.Int32 containing the hash code for the current instance.

System.Object.GetHashCode serves as a hash function for a specific type. A hash function is used to quickly generate a number (a hash code) corresponding to the value of an object. Hash functions are used with hashtables. A good hash function algorithm rarely generates hash codes that collide. For more information about hash functions, see The Art of Computer Programming , Vol. 3, by Donald E. Knuth. All implementations of System.Object.GetHashCode are required to ensure that for any two object references x and y, if x.Equals(y) == true, then x.GetHashCode() == y.GetHashCode(). Hash codes generated by System.Object.GetHashCode need not be unique. Implementations of System.Object.GetHashCode are not permitted to throw exceptions. The System.Object.GetHashCode implementation attempts to produce a unique hash code for every object, but the hash codes generated by this method are not guaranteed to be unique. Therefore, System.Object.GetHashCode may generate the same hash code for two different instances. It is recommended (but not required) that types overriding System.Object.GetHashCode also override System.Object.Equals(System.Object) . Hashtables cannot be relied on to work correctly if this recommendation is not followed. Use this method to obtain the hash code of an object. Hash codes should not be persisted (i.e. in a database or file) as they are allowed to change from run to run.

using System;
public struct Int32 {
 int value;
 //other methods...

 public override int GetHashCode() {
 return value;
 }
}

using System;
public struct Point {
 int x;
 int y; 
 //other methods
 
 public override int GetHashCode() {
 return x ^ y;
 }
}

using System;
public class SomeType {
 public override int GetHashCode() {
 return 0;
 }
}

public class AnotherType {
 public override int GetHashCode() {
 return 1;
 }
}

public class LastType {
 public override int GetHashCode() {
 return 2;
 }
}
public class MyClass {
 SomeType a = new SomeType();
 AnotherType b = new AnotherType();
 LastType c = new LastType();

 public override int GetHashCode () {
 return a.GetHashCode() ^ b.GetHashCode() ^ c.GetHashCode();
 }
}

using System;
public struct Int64 {
 long value;
 //other methods...

 public override int GetHashCode() {
 return ((int)value ^ (int)(value >> 32));
 }
}

public System.Type GetType()

Gets the type of the current instance.

Returns: The instance of System.Type that represents the run-time type (the exact type) of the current instance.

For two objects x and y that have identical run-time types, System.Object.ReferenceEquals(System.Object,System.Object)(x.GetType(),y.GetType()) returns true .

using System;
public class MyBaseClass: Object {
}
public class MyDerivedClass: MyBaseClass {
}
public class Test {
   public static void Main() {
   MyBaseClass myBase = new MyBaseClass();
   MyDerivedClass myDerived = new MyDerivedClass();

   object o = myDerived;
   MyBaseClass b = myDerived;

   Console.WriteLine("mybase: Type is {0}", myBase.GetType());
   Console.WriteLine("myDerived: Type is {0}", myDerived.GetType());
   Console.WriteLine("object o = myDerived: Type is {0}", o.GetType());
   Console.WriteLine("MyBaseClass b = myDerived: Type is {0}", b.GetType());
   }
}

protected System.Object MemberwiseClone()

Creates a shallow copy of the current instance.

Returns: A shallow copy of the current instance. The run-time type (the exact type) of the returned object is the same as the run-time type of the object that was copied.

System.Object.MemberwiseClone creates a new instance of the same type as the current instance and then copies each of the object's non-static fields in a manner that depends on whether the field is a value type or a reference type. If the field is a value type, a bit-by-bit copy of all the field's bits is performed. If the field is a reference type, only the reference is copied. The algorithm for performing a shallow copy is as follows (in pseudo-code): for each instance field f in this instance if (f is a value type) bitwise copy the field if (f is a reference type) copy the reference end for loop This mechanism is referred to as a shallow copy because it copies rather than clones the non-static fields. Because System.Object.MemberwiseClone implements the above algorithm, for any object, a, the following statements are required to be true: System.Object.MemberwiseClone does not call any of the type's constructors. If System.Object.Equals(System.Object) has been overridden, a.MemberwiseClone().Equals(a) might return false . For an alternate copying mechanism, see System.ICloneable . System.Object.MemberwiseClone is protected (rather than public) to ensure that from verifiable code it is only possible to clone objects of the same class as the one performing the operation (or one of its subclasses). Although cloning an object does not directly open security holes, it does allow an object to be created without running any of its constructors. Since these constructors may establish important invariants, objects created by cloning may not have these invariants established, and this may lead to incorrect program behavior. For example, a constructor might add the new object to a linked list of all objects of this class, and cloning the object would not add the new object to that list -- thus operations that relied on the list to locate all instances would fail to notice the cloned object. By making the method protected, only objects of the same class (or a subclass) can produce a clone and implementers of those classes are (presumably) aware of the appropriate invariants and can arrange for them to be true without necessarily calling a constructor.

using System;
class MyBaseClass {
   public static string CompanyName = "My Company";
   public int age;
   public string name;
}

class MyDerivedClass: MyBaseClass {

   static void Main() {
   
   //Create an instance of MyDerivedClass
   //and assign values to its fields.
   MyDerivedClass m1 = new MyDerivedClass();
   m1.age = 42;
   m1.name = "Sam";

   //Do a shallow copy of m1
   //and assign it to m2.
   MyDerivedClass m2 = (MyDerivedClass) m1.MemberwiseClone();
   }
}

+---------------+

|     42        |                           m1 

+---------------+

|     +---------|-----------------> "Sam" 

+---------------+                    /|\ 

                                      | 

+---------------+                     | 

|     42        |                     |      m2 

+---------------+                     | 

|      +--------|---------------------| 

+---------------+

public static System.Boolean ReferenceEquals(System.Object objA, System.Object objB)

Determines whether two object references are identical.

Parameter objA: First object to compare.

Parameter objB: Second object to compare.

Returns: True if a and b refer to the same object or are both null references; otherwise, false.

This static method provides a way to compare two objects for reference equality. It does not call any user-defined code, including overrides of System.Object.Equals(System.Object) .

using System;
class MyClass {
   static void Main() {
   object o = null;
   object p = null;
   object q = new Object();
   Console.WriteLine(Object.ReferenceEquals(o, p));
   p = q;
   Console.WriteLine(Object.ReferenceEquals(p, q));
   Console.WriteLine(Object.ReferenceEquals(o, p));
   }
}
   

public virtual System.String ToString()

Creates and returns a System.String representation of the current instance.

Returns: A System.String representation of the current instance.

System.Object.ToString returns a string whose content is intended to be understood by humans. Where the object contains culture-sensitive data, the string representation returned by System.Object.ToString takes into account the current system culture. For example, for an instance of the System.Double class whose value is zero, the implementation of System.Double.ToString might return "0.00" or "0,00" depending on the current UI culture. Although there are no exact requirements for the format of the returned string, it should as much as possible reflect the value of the object as perceived by the user. System.Object.ToString is equivalent to calling System.Object.GetType to obtain the System.Type object for the current instance and then returning the result of calling the System.Object.ToString implementation for that type. The value returned includes the full name of the type. It is recommended, but not required, that System.Object.ToString be overridden in a derived class to return values that are meaningful for that type. For example, the base data types, such as System.Int32, implement System.Object.ToString so that it returns the string form of the value the object represents. Subclasses that require more control over the formatting of strings than System.Object.ToString provides should implement System.IFormattable, whose System.Object.ToString method uses the culture of the current thread.

using System;

class MyClass {
   static void Main() {
      object o = new object();
      Console.WriteLine (o.ToString());
   }
}