asp.net complete lifecycle of a Web page

• Page request - During this stage, ASP.NET makes sure the page either parsed or compiled and a cached version of the page can be sent in response
• Start - During this stage sets the Request and Response page properties and the page check the page request is either a postback or a new request
• Page Initialization - During this stage, the page initialize and the control's Unique Id property are set
• Load - During this stage, if the request is postback, the control properties are loaded without loading the view state and control state otherwise loads the view state
• Validation - During this stage, the controls are validated
• Postback event handling - During this stage, if the request is a postback, handles the event
• Rendering - During this stage, the page invokes the Render method to each control for return the output
• Unload - During this stage, when the page is completely rendered and sent to the client, the page is unloaded.

Destructor in C#

Destructor is a special method that get invoked / called automatically whenever an object of a given class gets destroyed. Main idea behind using destructor is to free the memory used by the object.

Constructor in C#

Constructor is a special method that get invoked / called automatically whenever an object of a given class gets instantiated.

Interfaces in C#

An interface is similar to a class with method signatures. There wont be any implementation of the methods in Interface. Classes which implements interface should have implementation of methods defined in abstract class

Sealed Classes in c#

If a class is defined as Sealed it cannot be inherited in derived class.

public sealed class Car
{

public Car()
{
Console.WriteLine("Base Class Car");
}

public void DriveType()
{
Console.WriteLine("Right Hand ");
}
} 

Abstract Class in C#

If we don't want a class object to be created define the class as abstract. An abstract class can have abstract and non abstract classes. If a method in abstract id defined as abstract , it must be implemented in derived class. For example , in the classes given below , method DriveType is defined as abstract. 

abstract class Car
{
public Car()
{
Console.WriteLine("Base Class Car");
}
public abstract void DriveType();
}

class Ford : Car
{
public void DriveType()
{
Console.WriteLine("Right Hand ");
}
}

Method Hiding in C#

If the derived class doesn't want to use methods in base class , derived class can implement the same method in derived class with same signature. For example in the classes given below, DriveType() is implemented in the derived class with same signature. This is called Method Hiding.

class Car
{
public void DriveType()
{
Console.WriteLine("Right Hand Drive");
}
}

class Ford : Car
{
public void DriveType()
{
Console.WriteLine("Right Hand ");
}
}