.NET Tutorials, Forums, Interview Questions And Answers
Welcome :Guest
 
Sign In
Register
 
Win Surprise Gifts!!!
Congratulations!!!


Top 5 Contributors of the Month
david stephan

Home >> Interview Question >> .NET Framework >> Post New Question Subscribe to Interview Questions

What is a static class

Posted By :volvo     Posted Date :November 09, 2013    Points :40   Category :.NET Framework 
A static class is never instantiated. The static keyword on a class enforces that a type not be created with a constructor. In the static class, we access members directly on the type. This eliminates misuse of the class.

You can also find related Interview Question to What is a static class  below: 

Consider the following code:

public class Example extends Thread
{
public void run()
{
System.out.println ("Hello");
}

public static void main (String args[])
{
new Example();
}
}

Select the correct option regarding the preceding code ?

  
1, The code will not compile.
2, The code will compile but will not execute.
3, The code will compile, execute, and display Hello as the output.
4, The code will compile, execute, but will not display anything.

Answer : 4 (More...)

Consider the following two classes:

public class Example1
{
public static int num;
static
{
num=5;
}
}


public class Example2
{
public static void main(String[] args)
{
System.out.println(Example1.num);
}
}

Select the correct option regarding the preceding classes.?

  
1, The Example2 class will execute without any output.
2, The Example2 class will execute with the following output:5

3, The Example2 class will not compile as it does not calls the constructor of the Example 1 class.
4, The Example2 class will not execute as it does not calls the constructor of the Example 1 class.

Answer : 2 (More...)

What is the difference between a Struct and a Class?

  
The struct type is suitable for representing lightweight objects such as Point, Rectangle, and Color. Although it is possible to represent a point as a class, a struct is more efficient in some scenarios. For example, if you declare an array of 1000 Point objects, you will allocate additional memory for referencing each object. In this case, the struct is less expensive.

When you create a struct object using the new operator, it gets created and the appropriate constructor is called. Unlike classes, structs can be instantiated without using the new operator. If you do not use new, the fields will remain unassigned and the object cannot be used until all of the fields are initialized.

It is an error to declare a default (parameterless) constructor for a struct. A default constructor is always provided to initialize the struct members to their default values.

It is an error to initialize an instance field in a struct.

There is no inheritance for structs as there is for classes. A struct cannot inherit from another struct or class, and it cannot be the base of a class. Structs, however, inherit from the base class Object. A struct can implement interfaces, and it does that exactly as classes do.

A struct is a value type, while a class is a reference type. (More...)

Can we call a base class method without creating instance?

  
Its possible If its a static method.

Its possible by inheriting from that class also.

Its possible from derived classes using base keyword. (More...)

Difference between type constructor and instance constructor? What is static constructor, when it will be fired? And what is its use?

  
(Class constructor method is also known as type constructor or type initializer)
Instance constructor is executed when a new instance of type is created and the class constructor is executed after the type is loaded and before any one of the type members is accessed. (It will get executed only 1st time, when we call any static methods/fields in the same class.) Class constructors are used for static field initialization. Only one class constructor per type is permitted, and it cannot use the vararg (variable argument) calling convention. (More...)

What is Private Constructor? and it's use? Can you create instance of a class which has Private Constructor?

  
When a class declares only private instance constructors, it is not possible for classes outside the program to derive from the class or to directly create instances of it. (Except Nested classes)
Make a constructor private if:

1) You want it to be available only to the class itself. For example, you might have a special constructor used only in the implementation of your class' Clone method.

2) You do not want instances of your component to be created. For example, you may have a class containing nothing but Shared utility functions, and no instance data. Creating instances of the class would waste memory. (More...)

What is the difference between interface and abstract class ?

  
a class may inherit several interfaces, a class may inherit only one abstract class (More...)

Quick Links For Interview Questions Categories:
ASP.Net Windows Application   .NET Framework   C#   VB.Net   ADO.Net  
Sql Server   SharePoint   Silverlight   OOPs   JQuery   JavaScript/VBScript
Biztalk Patten/Practices .IIS WCF WPF WWF
Networking Aptitude Others   All      

Find questions, FAQ's and their answers related to .NET, C#, Vb.Net, Sql Server and many more.

 
Now you can find lots of .NET, C#, Vb.Net, SQL Server,Windows, ASP.Net related Questions and their Answers here at www.dotnetspark.com. Our aim is to help you pass your certification Exams (MCP, MCSD, MCAD etc.,) with flying scores and get good name in your company.

So, Start looking our Interview Question section daily and improve your .NET Skills. You can also help others by posting Interview Questions and their Answers in this section.


Hall of Fame    Twitter   Terms of Service    Privacy Policy    Contact Us    Archives   Tell A Friend