Overblog Follow this blog
Edit post Administration Create my blog
November 17 2010 4 17 /11 /November /2010 15:26

 

Design pattern FAQ Part 1 (Training)

Get Interview tutorials and videos on .NET 3.5, 4.0, Architecture,Design Pattern,Silverlight, SQL Server, CAS, Security, WCF, SharePoint, Azure, OOPS and many more on www.questpond.com

Introduction

Hi friends, please do not think you get an architecture position by reading interview questions. But yes there should be some kind of reference which will help you quickly revise what are the definition. Just by reading these answers you get to a position where you are aware of the fundamentals. But if you have not really worked you will surely fail with scenario based questions. So use this as a quick revision rather than a shot cut.

 

In case your are completely new to design patterns or you really do not want to read this complete   article do see our free design pattern Training and interview questions / answers videos.

 

  (B) What are design patterns?

Design patterns are documented tried and tested solutions for recurring problems in a given context. So basically you have a problem context and the proposed solution for the same. Design patterns existed in some or other form right from the inception stage of software development. Let’s say if you want to implement a sorting algorithm the first thing comes to mind is bubble sort. So the problem is sorting and solution is bubble sort. Same holds true for design patterns.

(I) Which are the three main categories of design patterns?

There are three basic classifications of patterns Creational, Structural, and Behavioral patterns.

Creational Patterns

Abstract Factory:- Creates an instance of several families of classes
Builder: - Separates object construction from its representation
Factory Method:- Creates an instance of several derived classes
Prototype:- A fully initialized instance to be copied or cloned
Singleton:- A class in which only a single instance can exist

Note: - The best way to remember Creational pattern is by remembering ABFPS (Abraham Became First President of States).
Structural Patterns

Adapter:-Match interfaces of different classes .
Bridge:-Separates an object’s abstraction from its implementation.
Composite:-A tree structure of simple and composite objects.
Decorator:-Add responsibilities to objects dynamically.
Façade:-A single class that represents an entire subsystem.
Flyweight:-A fine-grained instance used for efficient sharing.
Proxy:-An object representing another object.

Note : To remember structural pattern best is (ABCDFFP)
Behavioral Patterns

Mediator:-Defines simplified communication between classes.
Memento:-Capture and restore an object's internal state.
Interpreter:- A way to include language elements in a program.
Iterator:-Sequentially access the elements of a collection.
Chain of Resp: - A way of passing a request between a chain of objects.
Command:-Encapsulate a command request as an object.
State:-Alter an object's behavior when its state changes.
Strategy:-Encapsulates an algorithm inside a class.
Observer: - A way of notifying change to a number of classes.
Template Method:-Defer the exact steps of an algorithm to a subclass.
Visitor:-Defines a new operation to a class without change.

Note: - Just remember Music....... 2 MICS On TV (MMIICCSSOTV).
Note :- In the further section we will be covering all the above design patterns in a more detail manner.

(A) Can you explain factory pattern?

  • Factory pattern is one of the types of creational patterns. You can make out from the name factory itself it’s meant to construct and create something. In software architecture world factory pattern is meant to centralize creation of objects. Below is a code snippet of a client which has different types of invoices. These invoices are created depending on the invoice type specified by the client. There are two issues with the code below:-

  • First we have lots of ‘new’ keyword scattered in the client. In other ways the client is loaded with lot of object creational activities which can make the client logic very complicated.

    Second issue is that the client needs to be aware of all types of invoices. So if we are adding one more invoice class type called as ‘InvoiceWithFooter’ we need to reference the new class in the client and recompile the client also.






Figure: - Different types of invoice



Taking these issues as our base we will now look in to how factory pattern can help us solve the same. Below figure ‘Factory Pattern’ shows two concrete classes ‘ClsInvoiceWithHeader’ and ‘ClsInvoiceWithOutHeader’.

The first issue was that these classes are in direct contact with client which leads to lot of ‘new’ keyword scattered in the client code. This is removed by introducing a new class ‘ClsFactoryInvoice’ which does all the creation of objects.

The second issue was that the client code is aware of both the concrete classes i.e. ‘ClsInvoiceWithHeader’ and ‘ClsInvoiceWithOutHeader’. This leads to recompiling of the client code when we add new invoice types. For instance if we add ‘ClsInvoiceWithFooter’ client code needs to be changed and recompiled accordingly. To remove this issue we have introduced a common interface ‘IInvoice’. Both the concrete classes ‘ClsInvoiceWithHeader’ and ‘ClsInvoiceWithOutHeader’ inherit and implement the ‘IInvoice’ interface.

The client references only the ‘IInvoice’ interface which results in zero connection between client and the concrete classes ( ‘ClsInvoiceWithHeader’ and ‘ClsInvoiceWithOutHeader’). So now if we add new concrete invoice class we do not need to change any thing at the client side.

In one line the creation of objects is taken care by ‘ClsFactoryInvoice’ and the client disconnection from the concrete classes is taken care by ‘IInvoice’ interface
.




Figure: - Factory pattern

Below are the code snippets of how actually factory pattern can be implemented in C#. In order to avoid recompiling the client we have introduced the invoice interface ‘IInvoice’. Both the concrete classes ‘ClsInvoiceWithOutHeaders’ and ‘ClsInvoiceWithHeader’ inherit and implement the ‘IInvoice’ interface.


 

InterfaceAndConcrete.jpg

 


Figure :- Interface and concrete classes


We have also introduced an extra class ‘ClsFactoryInvoice’ with a function ‘getInvoice()’ which will generate objects of both the invoices depending on ‘intInvoiceType’ value. In short we have centralized the logic of object creation in the ‘ClsFactoryInvoice’. The client calls the ‘getInvoice’ function to generate the invoice classes. One of the most important points to be noted is that client only refers to ‘IInvoice’ type and the factory class ‘ClsFactoryInvoice’ also gives the same type of reference. This helps the client to be complete detached from the concrete classes, so now when we add new classes and invoice types we do not need to recompile the client.





Figure: - Factory class which generates objects

Note :- The above example is given in C# . Even if you are from some other technology you can still map the concept accordingly. You can get source code from the CD in ‘FactoryPattern’ folder.

(I) Can you explain abstract factory pattern?

Abstract factory expands on the basic factory pattern. Abstract factory helps us to unite similar factory pattern classes in to one unified interface. So basically all the common factory patterns now inherit from a common abstract factory class which unifies them in a common class. All other things related to factory pattern remain same as discussed in the previous question.

A factory class helps us to centralize the creation of classes and types. Abstract factory helps us to bring uniformity between related factory patterns which leads more simplified interface for the client.




Figure: - Abstract factory unifies related factory patterns

Now that we know the basic lets try to understand the details of how abstract factory patterns are actually implemented. As said previously we have the factory pattern classes (factory1 and factory2) tied up to a common abstract factory (AbstractFactory Interface) via inheritance. Factory classes stand on the top of concrete classes which are again derived from common interface. For instance in figure ‘Implementation of abstract factory’ both the concrete classes ‘product1’ and ‘product2’ inherits from one interface i.e. ‘common’. The client who wants to use the concrete class will only interact with the abstract factory and the common interface from which the concrete classes inherit.



Figure: - Implementation of abstract factory


Now let’s have a look at how we can practically implement abstract factory in actual code. We have scenario where we have UI creational activities for textboxes and buttons through their own centralized factory classes ‘ClsFactoryButton’ and ‘ClsFactoryText’. Both these classes inherit from common interface ‘InterfaceRender’. Both the factories ‘ClsFactoryButton’ and ‘ClsFactoryText’ inherits from the common factory ‘ClsAbstractFactory’. Figure ‘Example for AbstractFactory’ shows how these classes are arranged and the client code for the same. One of the important points to be noted about the client code is that it does not interact with the concrete classes. For object creation it uses the abstract factory ( ClsAbstractFactory ) and for calling the concrete class implementation it calls the methods via the interface ‘InterfaceRender’. So the ‘ClsAbstractFactory’ class provides a common interface for both factories ‘ClsFactoryButton’ and ‘ClsFactoryText’.




Figure: - Example for abstract factory



Note: - We have provided a code sample in C# in the ‘AbstractFactory’ folder. People who are from different technology can compare easily the implementation in their own language.

We will just run through the sample code for abstract factory. Below code snippet ‘Abstract factory and factory code snippet’ shows how the factory pattern classes inherit from abstract factory.



Figure: - Abstract factory and factory code snippet



Figure ‘Common Interface for concrete classes’ how the concrete classes inherits from a common interface ‘InterFaceRender’ which enforces the method ‘render’ in all the concrete classes.




Figure: - Common interface for concrete classes

 The final thing is the client code which uses the interface ‘InterfaceRender’ and abstract factory ‘ClsAbstractFactory’ to call and create the objects. One of the important points about the code is that it is completely isolated from the concrete classes. Due to this any changes in concrete classes like adding and removing concrete classes does not need client level changes.



Figure: - Client, interface and abstract factory

 

(I)Can you explain builder pattern?



Builder falls under the type of creational pattern category. Builder pattern helps us to separate the construction of a complex object from its representation so that the same construction process can create different representations. Builder pattern is useful when the construction of the object is very complex. The main objective is to separate the construction of objects and their representations. If we are able to separate the construction and representation, we can then get many representations from the same construction.


Figure: - Builder concept


To understand what we mean by construction and representation lets take the example of the below ‘Tea preparation’ sequence.

You can see from the figure ‘Tea preparation’ from the same preparation steps we can get three representation of tea’s (i.e. Tea with out sugar, tea with sugar / milk and tea with out milk).


Figure: - Tea preparation


Now let’s take a real time example in software world to see how builder can separate the complex creation and its representation. Consider we have application where we need the same report to be displayed in either ‘PDF’ or ‘EXCEL’ format. Figure ‘Request a report’ shows the series of steps to achieve the same. Depending on report type a new report is created, report type is set, headers and footers of the report are set and finally we get the report for display.

Figure: - Request a report

Now let’s take a different view of the problem as shown in figure ‘Different View’. The same flow defined in ‘Request a report’ is now analyzed in representations and common construction. The construction process is same for both the types of reports but they result in different representations.



Figure: - Different View


We will take the same report problem and try to solve the same using builder patterns. There are three main parts when you want to implement builder patterns.

Builder: - Builder is responsible for defining the construction process for individual parts. Builder has those individual processes to initialize and configure the product.
Director: - Director takes those individual processes from the builder and defines the sequence to build the product.
Product: - Product is the final object which is produced from the builder and director coordination.

First let’s have a look at the builder class hierarchy. We have a abstract class called as ‘ReportBuilder’ from which custom builders like ‘ReportPDF’ builder and ‘ReportEXCEL’ builder will be built.

Figure: - Builder class hierarchy

 

Figure ‘Builder classes in actual code’ shows the methods of the classes. To generate report we need to first Create a new report, set the report type (to EXCEL or PDF) , set report headers , set the report footers and finally get the report. We have defined two custom builders one for ‘PDF’ (ReportPDF) and other for ‘EXCEL’ (ReportExcel). These two custom builders define there own process according to the report type.

 

Figure: - Builder classes in actual code

Now let’s understand how director will work. Class ‘clsDirector’ takes the builder and calls the individual method process in a sequential manner. So director is like a driver who takes all the individual processes and calls them in sequential manner to generate the final product, which is the report in this case. Figure ‘Director in action’ shows how the method ‘MakeReport’ calls the individual process to generate the report product by PDF or EXCEL.

 

 



Figure: - Director in action

 

 

The third component in the builder is the product which is nothing but the report class in this case.

 

 

Figure: - The report class

 

Now let’s take a top view of the builder project. Figure ‘Client,builder,director and product’ shows how they work to achieve the builder pattern. Client creates the object of the director class and passes the appropriate builder to initialize the product. Depending on the builder the product is initialized/created and finally sent to the client.

 

 

 


Figure: - Client, builder, director and product

 

 

The output is something like this. We can see two report types displayed with their headers according to the builder.

 

 

Figure: - Final output of builder

 


Note :- In CD we have provided the above code in C# in ‘BuilderPattern’ folder.

 

 

(I) Can you explain prototype pattern?

 

Prototype pattern falls in the section of creational pattern. It gives us a way to create new objects from the existing instance of the object. In one sentence we clone the existing object with its data. By cloning any changes to the cloned object does not affect the original object value. If you are thinking by just setting objects we can get a clone then you have mistaken it. By setting one object to other object we set the reference of object BYREF. So changing the new object also changed the original object. To understand the BYREF fundamental more clearly consider the figure ‘BYREF’ below. Following is the sequence of the below code:

  • In the first step we have created the first object i.e. obj1 from class1.
  • In the second step we have created the second object i.e. obj2 from class1.
  • In the third step we set the values of the old object i.e. obj1 to ‘old value’.
  • In the fourth step we set the obj1 to obj2.
  • In the fifth step we change the obj2 value.
  • Now we display both the values and we have found that both the objects have the new value.

Figure :- BYREf

 

 

The conclusion of the above example is that objects when set to other objects are set BYREF. So changing new object values also changes the old object value.

There are many instances when we want the new copy object changes should not affect the old object. The answer to this is prototype patterns.

Lets look how we can achieve the same using C#. In the below figure ‘Prototype in action’ we have the customer class ‘ClsCustomer’ which needs to be cloned. This can be achieved in C# my using the ‘MemberWiseClone’ method. In JAVA we have the ‘Clone’ method to achieve the same. In the same code we have also shown the client code. We have created two objects of the customer class ‘obj1’ and ‘obj2’. Any changes to ‘obj2’ will not affect ‘obj1’ as it’s a complete cloned copy.

 





Figure: - Prototype in action

 

 


Note :- You can get the above sample in the CD in ‘Prototype’ folder. In C# we use the ‘MemberWiseClone’ function while in JAVA we have the ‘Clone’ function to achieve the same.

(A) Can you explain shallow copy and deep copy in prototype patterns?

 

There are two types of cloning for prototype patterns. One is the shallow cloning which you have just read in the first question. In shallow copy only that object is cloned, any objects containing in that object is not cloned. For instance consider the figure ‘Deep cloning in action’ we have a customer class and we have an address class aggregated inside the customer class. ‘MemberWiseClone’ will only clone the customer class ‘ClsCustomer’ but not the ‘ClsAddress’ class. So we added the ‘MemberWiseClone’ function in the address class also. Now when we call the ‘getClone’ function we call the parent cloning function and also the child cloning function, which leads to cloning of the complete object. When the parent objects are cloned with their containing objects it’s called as deep cloning and when only the parent is clones its termed as shallow cloning.

 

 

Figure: - Deep cloning in action

(B) Can you explain singleton pattern?

 

There are situations in a project where we want only one instance of the object to be created and shared between the clients. No client can create an instance of the object from outside. There is only one instance of the class which is shared across the clients. Below are the steps to make a singleton pattern:-

1) Define the constructor as private.
2) Define the instances and methods as static.

Below is a code snippet of a singleton in C#. We have defined the constructor as private, defined all the instance and methods using the static keyword as shown in the below code snippet figure ‘Singleton in action’. The static keyword ensures that you only one instance of the object is created and you can all the methods of the class with out creating the object. As we have made the constructor private, we need to call the class directly.

 

Figure: - Singleton in action

 

Note :- In JAVA to create singleton classes we use the STATIC keyword , so its same as in C#. You can get a sample C# code for singleton in the ‘singleton’ folder.

(A) Can you explain command patterns?

Command pattern allows a request to exist as an object. Ok let’s understand what it means. Consider the figure ‘Menu and Commands’ we have different actions depending on which menu is clicked. So depending on which menu is clicked we have passed a string which will have the action text in the action string. Depending on the action string we will execute the action. The bad thing about the code is it has lot of ‘IF’ condition which makes the coding more cryptic.

 


Figure: - Menu and Commands

 

Command pattern moves the above action in to objects. These objects when executed actually execute the command.
As said previously every command is an object. We first prepare individual classes for every action i.e. exit, open, file and print. Al l the above actions are wrapped in to classes like Exit action is wrapped in ‘clsExecuteExit’ , open action is wrapped in ‘clsExecuteOpen’, print action is wrapped in ‘clsExecutePrint’ and so on. All these classes are inherited from a common interface ‘IExecute’.

 


Figure: - Objects and Command

 

Using all the action classes we can now make the invoker. The main work of invoker is to map the action with the classes which have the action.
So we have added all the actions in one collection i.e. the arraylist. We have exposed a method ‘getCommand’ which takes a string and gives back the abstract object ‘IExecute’. The client code is now neat and clean. All the ‘IF’ conditions are now moved to the ‘clsInvoker’ class.

 

Figure: - Invoker and the clean client

Note: - You can find a sample code for C# code in command pattern in ‘Command’ folder.

Other Interview question PDF's

.NET Interview Question PDF

Share this post

Repost 0
Published by questpond.over-blog.com
write a comment

comments

Important .NET and C# interview questions and answers

.Net interview questions: - Explain why it is not preferred to use finalize for clean up?

.Net interview questions: - Show the five levels in CMMI?

.NET interview questions and answers: – Which is the best place to store connection string in .NET projects?

C# interview questions and answers: – Explain the use of Icomparable in c#?

C# interview questions: - How can we check which rows have changed since dataset was loaded?

C# interview questions and answers: - Can you write a simple c# code to display Fibonacci series?

.NET interview questions and answers: - What is difference betweenIcomparable VS Icomparer ?

C# and .NET interview question: -What is short circuiting in C#?

C# and .NET interview question: - What are symmetric and asymmetric algorithms?

Important c# and .NET interview question on object pooling and Gridview events?

.NETinterview questions and answers: – Will the finally run in this code?

How to prepare for c# and .NETinterviews?

C# and .NET Interview questions: - What is Thread.Join () in threading?

.NET Interview questions and answers: -What is serialization and deserialization in .NET?

C# and .NET interview question: - What is hashing?

c# and .NET interview question:- what connects dataset and data source ?

.Net interview questions and answers: - What is the difference between “Web.config” and “Machine.Config”?

.NET interview questions and answers: - What is TPL?

.NET Interview questions and answers: -What are different access modifiers?

.NET and c# Interview Question and answers: – If we want to update interface with new methods, what is the best practice?

 MVC ( Model view controller) interview questions and answers      

ASP.NET Application and Page Life Cycle 

12 Important FAQ’s on VSTS Testing (Unit testing, load testing, automated testing, database testing and code coverage) 

 6 important use of Partial/Mock testing

6 important uses of Delegates and Events

7 Simple Steps to Run Your First Azure Blob Program

8 Steps to Create Workflows using SharePoint Designer

Azure FAQ Part 1

C# Code Reviews using StyleCop – Detailed Article

Four real world uses of Partial classes and Partial methods

SharePoint Quick Start FAQ Part 1

SharePoint Quick Start FAQ Part 6 – Workflows, Workflows and Workflows

SharePoint Workflow Basics

 

 

 

 

MVC Interview questions videos

Viewdata,viewbag,tempdata

 

MVC asynch controllers

What is View Model in ASP.NET MVC?



ADO.NET interview questions videos



Explain ADO.NET Connection pooling

 

 

Windows Phone Application Questions Videos

 

How to create a simple windows phone application ?

 

 

MVC Interview questions and answers Article

 

(Model view controller)MVC Interview questions and answers

MVC interview questions with answers video: – What is Web API how to implement the same?

ASP.Net MVC  4 interview questions with answers: - What is Bundling and minification in Model view controller ?

MVC interview questions with answers :- Is it possible to return values instead of Actionresults?

MVC interview questions with answers :- What are the actionresults available in MVC?

MVC interview questions with answers:-Html.PartialvsHtml.RenderPartialvsHtml.RenderPage in MVC

MVC ASP.NET INTERVIEW QUESTIONS WITH ANSWERS :- WHAT IS THE DIFFERENCE BETWEEN VIEWSTATE VS VIEWDATA ?

MVC vs ASP.NET ( MVC Interview question with answers )?

How can we detect that a MVC controller is called by POST or GET ? ( ASP.NET MVC Interview questions with answers)

What are the different ways by which you will get Form Data in controller? ( MVC Interview questions with answers)

What is the difference between Presenter and Controller in MVC?(MVC interview questions with answers)

Learn MVC (Model view controller) Step by Step in 7 days – Day 4

MVC Interview questions and answers PDF

MVC interview questions with answers

ActionResult vs. View() vs. ViewResult :- MVC interview questions with answers

Explain Areas in MVC?( MVC interview questions with answers)

Can you explain the purpose of ViewModel in MVC?( ASP.NET MVC Interview questions with answers)

ASP.NET MVC interview questions: - What are Filters in MVC?

What are areas in MVC?( MVC Interview questions with answers)

Explain the concept of View Model in MVC?

Exception Handling in MVC

Explain MVC application life cycle?


100 MVC Interview question PDF download released , Enjoy


Learn Microsoft Business intelligence step by step – Day 1


Can you create TempBag just like ViewBag?( MVC Interview questions)


MVC Unit Testing Unleashed

MVC and .NET learning tutorials for components of MVC and how do you perform unit testing in MVC?

Explain MVC model binders ? ( ASP.NET MVC interview questions)

Explain the difference between layout and master pages ? (MVC Razor interview questions)

Advantages of ViewModel in MVC(Model View Controller)

Difference Between ViewResult() and ActionResult() in MVC ?

What is the difference between each version of MVC 2, 3, 4, 5 and 6? (MVC Interview Questions)

Learn ASP.NET MVC 5 Step by Step in 30 days – Day 1

Can we overload MVC controller action methods ? (MVC Polymorphism) 

Can we overload Actions / Controllers in MVC? (MVC Interview questions)

 


WCF Interview questions videos

 

overloading in WCF

WCF fault exceptions ?

 

 

 

 

WPF Interview question with answers videos

 

Why WPF and compare WPF with Winforms ?

 

 

C# Interview Questions & Answers Article

 

12 Important FAQ’s on VSTS Testing (Unit testing, load testing, automated testing, database testing and code coverage)

6 important use of Partial/Mock testing

6 important uses of Delegates and Events

7 Simple Steps to Run Your First Azure Blob Program

8 Steps to Create Workflows using SharePoint Designer

Azure FAQ Part 1

C# Code Reviews using StyleCop – Detailed Article

Four real world uses of Partial classes and Partial methods

SharePoint Quick Start FAQ Part 1

SharePoint Quick Start FAQ Part 6 – Workflows, Workflows and Workflows

SharePoint Workflow Basics

C# (Csharp) interview questions and answers: – What are indexers in .NET?

C# OOP interview questions and answers: - I do not want to implement all the interface methods?

C# design pattern (UNIT of Work Design Pattern)

C# design pattern interview questions – What is Dependency injection ?

C# interview questions and answers: - What is the difference between “==” and .Equals()?

How questions are asked in c# interviews?

C# design pattern interview question: - DI vs IOC

8 important C# Interview questions on IL code, JIT, CLR, CTS, CLS and CAS

What is the difference between Reflection and Dynamic in C#?

C# and .NET interview question: – When should we use Structure as compared to classes
?

C# REST interview questions with answers asked in Polaris Hydrebad

c# threading interview questions :- Parallel.ForEach vs Task.Factory.StartNew

C# circular dependency interview questions with answers.

C# Design pattern interview questions with answers: - How Singleton is different from Static class?

C# and .NET interview questions with answers: - How can we mark a method as deprecated?

C# INTERVIEW QUESTIONS WITH ANSWERS: - HOW TO ASSIGN MULTILINE STRING IN VISUAL STUDIO?

What is cyclomatic complexity (C# testing interview questions with answers)?

Define code coverage? (C# unit testing interview questions with answers)

Can you talk about Abstraction and Encapsulation in detail ? ( .NET, c# and OOP interview questions with answers )

Can you explain a practical example of virtual and Override? ( C# OOP interview questions with answers )

Can you explain class and object in real time scenario? ( C# and .NET OOP Interview questions with answers)

What is code digger ? ( C# visual studio interview questions with answers)

C# Lazy loading interview questions with answers

What is eager loading in c# ( C# eager loading interview questions with answers)?

Can you explain the term concurrency? (C# Interview questions with answers)

10 important C# Constructor and destructor interview questions

3 important c# Partial class interview questions with answers

Change Functionality without changing function( C# Architecture interview question with answers)?

What is ENUM and what are the benefits of using it (ENUM C# Interview Question 1)?

How can we loop through ENUM values( C# ENUM Interview questions with answers)?

What is the difference between Connection Timeout and Command Timeout?( C# ADO.NET Interview questions with answers)

How you differentiate Shadowing with Overriding? (C# overriding interview questions)

C# date and time interview question with answers

Explain the difference between early binding and late binding? ( C# interview questions with answers)

How can we restrict types in generics ?( C# generic interview questions)

What are generics, Delegates and Generic delegates ( C# interview questions)?

How can we convert JSON string in to c# object?(  C# JSON interview questions)

C# and .NET interview questions asked in TCSwalkin.

C# and .NET interview questions on Coalescing operator.

String vs string ( C# interview questions with answers)

Explain SOLID principles (C# Architecture interview questions)?

C# and .NET interview questions around Read only and Constant

C# Architecture interview questions with answers

C# Mock testing interview questions and answers: – What is Mock testing and how can we implement Mocking?

Write a simple regex for email validation? (C# interview questions with answers)


C#.NET interview questions: - What is the use of “Yield” keyword? Mention atleast one practical scenario where it can be used?

C#.NET interview questions: - What is the difference between Build Vs Rebuild Vs Clean solution menu? What is the difference “Rebuild” and if you do “Clean” + “Build”?

C# and .NET interview questions around JIT and NGEN


What is the difference between throw vs throw ex ?( C# Interview questions with answers)

C#/.NET interview questions: - What are the steps included to get a collection of records from database in C#?


Learn C# in Hindi video tutorials


QuestPond’s real life examples on Extension methods and nullable types in C#.NET


Why Microsoft has partial classes and Java does not?

 

 

 

WCF INTERVIEW QUESTIONS AND ANSWERS ARTICLE

 

 

WCF INTERVIEW QUESTIONS AND ANSWERS: - WHAT IS THE DIFFERENCE BETWEEN SERVICE ENDPOINT AND CLIENT ENDPOINT

 

WCF INTERVIEW QUESTIONS WITH ANSWERS: - WCF REST VS. WEB API

 

WCF INTERVIEW QUESTIONS WITH ANSWERS :- CAN WE HAVE METHOD OVERLOADING WHILE DEFINING WCF SERVICE OPERATIONS ?

 

WCF INTERVIEW QUESTIONS WITH ANSWERS :- WHAT IS DATACONTRACTSERIALIZER AND HOW IT’S DIFFERENT FROM XMLSERIALIZER 

What is SOA and what is WCF? ( WCF interview questions with answers)

Six important WCF interview questions with answers

6 important WCF Instancing interview questions with answers

WCF Service metadata interview questions with answers

7 WCF SOA interview questions with answers

What are the various ways of consuming WCF services?(WCF C# interview questions with answers)

What is the difference between Serialization and Encoding in WCF?( WCF interview questions with answers)

Why returning dataset or data table from WCF service is not a good practice?(WCF service interview questions with answers)

WCF transaction interview questions: - How transaction works in WCF?

WCF Transaction interview questions.

.NET WCF(Windows Communication Foundation) interview questions: - Distinguish between Web Services and Remoting | WCF and Web services

WCF interview questions: - What exactly do you mean by Single in WCF instancing? How to set and what is by default set value of instance context mode?

Explain WCF Duplex services? ( WCF Interview questions)

QuestPond: Interview Questions and Answers on learning WCF

WCF Interview Questions: - What are the different ways of doing WCF concurrency and WCF instancing?

QuestPond: Interview Questions and Answers on learning WCF (Windows Communication Foundation)

QuestPond: Interview Questions and Answers on learning WCF (Windows Communication Foundation)

QuestPond: Interview Questions and Answers on WCF(Windows Communication Foundation)

QuestPond: Interview Questions and Answers on learning WCF (Windows Communication Foundation)

QuestPond’s Interview Questions & Answers on learning data contract serializer and XML serializer

QuestPond’s Interview Questions & Answers on learning serialization events

QuestPond’s Interview Questions & Answers on learning WCF(Windows Communication Foundation)

QuestPond’s Interview Questions & Answers on WCF(Windows Communication Foundation)


QuestPond’s Interview Questions & Answers on WCF(Windows Communication Foundation)

QuestPond’s Interview Questions & Answers on WCF (Windows Communication Foundation)


QuestPond’s Interview Questions & Answers on WCF (Windows Communication Foundation)

 

 

 

WPF Interview Questions And Answers Article

 

 

6 IMPORTANT WPF AND SILVERLIGHT MULTI-THREADING INTERVIEW QUESTIONS WITH ANSWERS

 

C# WPF INTERVIEW QUESTIONS::- WHAT ARE DEPENDENCY PROPERTIES ?

 

WPF INTERVIEW QUESTIONS WITH ANSWERS: – WHAT ARE WPF CONVERTERS?

 

WPF INTERVIEW QUESTIONS ON EVENTS (TUNNELING, BUBBLING AND DIRECT)

 

What are the advantages of using WPF ( WPF interview questions with answers)?

 

Explain WPF bindings?( .Net WPF Binding interview questions)

 

WPF Interview questions with answers :-What is XAML in WPF and why do we need it?

 

What are the different kinds of controls in WPF?(C# WPF Interview questions with answers)

 

Can you explain the complete WPF object hierarchy?(WPF Interview questions with answers)

How does “UpdateSourceTrigger” affect bindings?( C# WPF interview questions with answers)

WPF Interview questions :- Which are the different namespaces and classes in WPF ?

What are resources in WPF? (C# WPF Interview questions with answers)

Explain multi binding and multivalue converters? (.NET WPF  Interview questions with answers)

Explain the difference between static and dynamicresource? (.NET WPF interview questions)

18 important WPF interview questions asked in WPF interviews.

.NET WPF(Windows Presentation Foundation) interview questions: - What is WPF? What are the advantages of WPF over Winforms?

Explain WPF relative binding / relative resource? (.NET WPF Interview questions with answers)

Explain Ancestor relative source binding in WPF ? ( WPF Interview questions with answers)

Explain the need of binding and commands?(WPF Interview questions)

Can you explain WPF command with an example? ( WPF Interview questions with answers)

Explain the need of “INotifyPropertyChanged” interface? ( C# WPF Interview questions with answers)

What is MVVM? (WPF MVVM Interview questions)

What is the importance of command and bindings in MVVM pattern? ( WPF MVVM Interview questions)

What is the difference between MVVM and 3 layer architecture? ( WPF  MVVM Interview questions with answers)

Explain delegate command? (WPF MVVM interview questions)

WPF Interview questions with answers

Explain WPF styles?(C# WPF Interview questions with answers)

Explain Multitrigger concept in WPF?( C# WPF Interview questions with answers)

How are WPF observable collections different from simple .NET collections? (.NET WPF Interview questions)

What is the difference between control templates and data templates? ( .NET WPF Interview questions)

What are various ways of doing alignment in WPF?( WPF Interview questions with answers)

 

Algorithm Interview Questions


Algorithm interview questions and answers: – Can you write code for bubble sort algorithm?

Algorithm interview questions and answers: – What is inserted sort algorithm?

SQL INTERVIEW QUESTIONS & ANSWERS ARTICLE

 

SQL Server Interview Questions & Answers Article

SQL Server interview questions and answers: - What is HID data type in SQL Server ?

SQL Server interview questions with answers: – How to get the top record without using max, top and order by keyword?

SQL Server interview questions with answers :- If you wish to store financial values which SQL Server data type is more suitable ?

SQL Server interview questions and answers: – What is the difference between Candidate Key, Primary Key, and Alternate Key

SQL Server interview questions with answers :- What are Indexes in Sql Server?

How to sort interactively using SSRS? (SQL Server reporting services interview questions)

How to do conditional formatting in SSRS? (SQL Server reporting services interview questions with answers)

WHAT IS NORMALIZATION AND EXPLAIN 1NF 2NF AND 3NF IN SIMPLE WORDS? SQL SERVER INTERVIEW QUESTIONS WITH ANSWERS

What is the difference between Stored Procedures and Function (SQL Server interview question with answers)?

 

When you will use inner join and when you will use outer join? SQL Server interview questions with answers

 

Do you know anything about Temporary procedures in SQL?( SQL Server interview questions with answers)

 

4 SQL Server interview questions with answers on TempTb

 

Are full outer join and Cross join are same? ( SQL Server interview questions with answers)

 

Delete duplicate records: - SQL Server interview questions with answers

 

4 most asked  SQL queries during SQL Serverinterview’s

 

How Temporary tables are different from normal tables and what are its types ?( SQL Server interview questions with answers)

 

SQL Server interview Questions on JOIN’s

 

SQL Server interview questions: - How can you increase SQL performance?

 

SQL Server interview questions: - What problem you face if locking is not implemented?

 

Can we insert NULL’s in to UNIQUE key ? ( SQL Server  interview questions with answers)

 

Explain Normalization?(SQL Server Interview questions with answers)

Temp variablesVS Temp tables(SQL Server interview questions)

 


 




.NET INTERVIEW QUESTIONS & ANSWERS ARTICLE

 

.NET interview questions and answers: - How to reverse a string in .NET ( DotNet)?

.NET interview questions and answers: - What is the use of Click Once?

.NET interview questions and answers: - Will the below codes create new instances?

C# and .NET interview questions with answers – What is Nuget?

Dependency injection (DI) VS Inversion of Control (IOC)

.NET interview questions with answers: - What is the difference between Reflection and Dynamic?

Five Great .NET Framework 4.5 Features

ASP.NET MVC 4 interview questions with answers: - What is the use of “AllowHTML” and “ValidateInput” attributes?

.NET interview questions 6th edition (Sixth edition) - By Shivprasad Koirala

.NET interview questions with answers: – Can we use events without delegates ?

.Net Interview question Edition 6 is available now.

.NET interview questions with answers: – What’s the difference between catch with parameter and catch without parameter?

.NET interview questions : - What is the use and difference between “IS” and “AS” keyword?

.NET interview questions with answers: - Build solution VS Rebuild solution VS Clean solution

HTML 5 interview questions with answers for LocalStorage and SessionStorage

.NET 4.0 interview questions with answers: – What are code contracts?

What are portable class libraries? ( .NET interview questions with answers)

How to loop through ENUM using C# (.NET interview questions with answers)?

What are transactions in C#? (.NET interview questions with answers)

What are ACID Properties( .NET Interview questions with answers)?

.NET interview questions: – What are the areas that need to be concentrated for senior(9+ years experience)persons in .NET technologies?

.NET interview questions: - Explain real time scenarios in Factory Pattern, Abstract Pattern, Singleton, WCF and REST services

What is the difference between IS A and Can a Relationship?( .NET Interview questions with answers)

What is the use of ENUM Flags(.NET Enum Interview question 2)?

What is the difference between .Net,C#, Asp.net, Asp.net Web Forms and Asp.net MVC and MVC?( C# and ASP.NET Interview questions)

ADO.NET interview questions: - Explain in detail the fundamental of connection pooling?

.NET interview questions: – Can you explain generics in .NET?

What are Properties and methods ? ( .NET OOP Interview questions with answers)

What’s the first step you take for implementing any of Design Pattern?( .NET  Design pattern interview questions with answers)

.NET interview questions: - What are different types of JIT?

ADO.NET Interview Question: - What are the major differences between classic ADO and ADO.NET?

.NET interview questions: – What is the difference between Reflection and Dynamic?

What is the Use of interfaces?( .NET Interview questions with answers)

.NET interview questions: - What role did you play in your project and company?

Visual studio 2012 Fakes

.NET interview questions: - So how can we clean unmanaged objects and also maintain performance?

ADO.NET Interview Questions: - What are basic methods of Data adapter?

.NET interview questions: - What are system level exceptions and application level exceptions?

.NET interview questions: - What is UML and which are the important diagrams?

.NET interview questions: - What is time out support in regex (regular expression)?

.NET interview questions: - How can we improve performance of .NET?

.NET interview questions: - Can you explain the concept of “Short Circuiting”?

.NET interview questions: - Can you explain Forms authentication in detail?

What is the difference between VAR and Dynamic keyword? ( .NET Interview questions with answers)

.NET interview questions: - What are similarities and difference between Class and structure?

Can you compare String.IsNullOrEmpty vs String.IsNullOrWhiteSpace ? ( .Net Interview questions with answers)

.NET interview questions: - Distinguish between Reflection and Dynamic?

.NET interview questions: - In which scenarios we can use serialization and when to use what binary serialization or XML serialization?

.NET interview questions: - Are there any readymade objects in .NET by which we can implement Lazy loading?

.NET interview questions: - What are different access modifiers?

ADO.NET interview questions: - Explain in detail the fundamental of connection pooling how to enable and disable connection pooling?

ADO.NET interview questions: - What is the namespace in which .NET has the data functionality class?

ADO.NET interview questions: - What are the different components in ADO.NET?

ADO.NET interview questions: - Show difference between “Optimistic” and “Pessimistic” locking and how many ways are there to implement optimistic locking in ADO.NET?

.NET interview questions: - Does code contract only do dynamic checks?

ADO.NET interview questions: - How can we fire a simple SQL Statement using ADO.NET?

.NET interview questions: - What basic steps are needed to display a simple report in crystal?

ADO.NET interview questions: - What are basic methods of Data adapter and mention the use of data adapter?

.NET interview questions: - What is UML? How many types of diagrams are there in UML?

.Net Interview Questions - What is MVC, MVP and MVVM pattern?

.NET interview questions: - How can you define a property read only for external world and writable in the same assembly?

Explain the implicit and explicit conversion of data types with examples?( .NET interview questions on data type)

.NET interview questions: - What is Reflection its implementation and practical uses?

What is downcasting and upcasting? (.NET interview questions with answers)

.NET interview questions: - How to decide on the design consideration to take a Data grid, data list or repeater?

.NET interview questions: - If we want to update interface with new methods, what is the best practice?

.NET interview questions: - How does selection sort algorithm works?

XML(.NET) interview questions: - What is XML?

.NET Interview questions: - If a validation is very complex what will you do?

.NET interview questions: - How can we stop the class from further inheriting?

XML (.NET) Interview questions :- Explain simple Walk through of XmlReader.

.NET interview questions : - How can we improve performance of .NET and show the difference between .NET 1.X, 2.0, 3.0, 3.5 and 4.0?

How to convert string to ENUM value ?( .NET interview questions with answers)

.NET architecture interview questions series: - What is mean by modeling language?

.NET architecture interview questions : - What are benefits and Limitation of using Viewstate, hidden frames and Cookies?

.NET interview questions: - What is GAC (Global Assembly Cache)?

.NET interview questions: - Explain Nuget?

.NET Testing interview questions: - What is the difference between Unit testing, Assembly testing and Regression testing?


.NET interview questions: - What is Code Access Security (CAS) and how does it work? Is CAS supported in .NET 4.0?


.NET interview questions: - What are the advantages /disadvantages of lazy loading?


.NET interview questions: - What is the use of DEBUG directive?


.NET testing interview questions: - What is Mock testing and how to implement it?


.NET interview questions: - What is the difference between DEBUG and Release?


.NET testing interview questions: - How can we UNIT test private methods using VSTS? Is it good to practice to UNIT test Private methods?


Explain 3 layer architecture ( .NET Interview questions)?


.NET interview questions : - What is a delegate and how can we create a delegate? What is a multicast delegate?


ADO.NET interview questions: - How to add/remove row is in “Data Table” object of “Dataset”? How to load multiple tables in a Dataset & adding relation between tables in a Dataset?


What is the difference between Array, ArrayList and List?( .Net Interview questions)

.NET interview questions: - How to implement DTC in .NET?
.NET interview questions: - What is an Interface and what are abstract classes

.NET interview questions: - Interface vs. abstract class

.NET interview questions: - How to implement practically Lazy loading in .NET?


.NET interview questions: - How can we handle exceptions in .NET? What if we do not catch the exception?

.NET interview questions based on Projects.


.NET interview questions: - What is shadowing? What is the difference between Shadowing and Overriding?

.NET interview questions: - All about Design Patterns in .NET


.NET interview questions: - How can we improve performance of .NET/ASP.NET/SQL Server?

.NET interview questions: - What benefits does sealed keyword provide?


.NET Architecture UML interview question


.NET interview questions: - How to maintain performance and can clean unmanaged objects?


.NET interview questions: - Explain ENUM and its benefits? What is the use of Flagsin ENUM?

.NET interview questions: - How to create a windows service using .NET?

.NET interview questions: - Explain in details about Indexer and can we have static indexer in C#?

.NET interview questions: - What is the difference between arraylist and list? Are Arraylist faster or Arrays?

.NET interview questions: - What is Native Image Generator (Ngen.exe)? Does NGEN.EXE always improve performance?

.NET OOPS interview questions: - What is OOP? What are different properties provided by Object-oriented systems?

.NET OOPS interview questions: - How abstract with only abstract method is it different from interfaces? Also mention best practice to update interface with new methods?

.NET interview questions: - What is the difference between delegate and events? Can we have return type, access modifiers and shared events?

.NET interview questions: - What is Manifest? Where is the version information stored of an assembly? Is versioning applicable to private assemblies?

.NET Generics interview questions: - Explain Generics and concept of Generic Collection in .NET?

How to learn .NET: - In parent-child relationship which constructor will fire first and in which instances you will declare a constructor private?

Basics of .NET and learning tutorials on CTS and CLS


Online resource to learn .NET on Reflection and Dynamic

Online guide to learn .NET for Object initializer in C#?

QuestPond for Freshers on IL code, JIT, CLR, CTS, CLS and CAS

QuestPond: Interview Questions and Answers on AJAX and how does it help?



ASP.NET Interview Questions & Answers Article










MVC Interview Questions And Answers Article

 

(MODEL VIEW CONTROLLER)MVC INTERVIEW QUESTIONS AND ANSWERS

 

MVC INTERVIEW QUESTIONS WITH ANSWERS VIDEO: – WHAT IS WEB API HOW TO IMPLEMENT THE SAME?

 

ASP.NET MVC  4 INTERVIEW QUESTIONS WITH ANSWERS: - WHAT IS BUNDLING AND MINIFICATION IN MODEL VIEW CONTROLLER ?

 

MVC INTERVIEW QUESTIONS WITH ANSWERS :- IS IT POSSIBLE TO RETURN VALUES INSTEAD OF ACTIONRESULTS?

 

MVC INTERVIEW QUESTIONS WITH ANSWERS :- WHAT ARE THE ACTIONRESULTS AVAILABLE IN MVC?

 

MVC INTERVIEW QUESTIONS WITH ANSWERS:-HTML.PARTIALVSHTML.RENDERPARTIALVSHTML.RENDERPAGE IN MVC

MVC VS ASP.NET ( MVC INTERVIEW QUESTION WITH ANSWERS )?

 

HOW CAN WE DETECT THAT A MVC CONTROLLER IS CALLED BY POST OR GET ? ( ASP.NET MVC INTERVIEW QUESTIONS WITH ANSWERS)

 

WHAT ARE THE DIFFERENT WAYS BY WHICH YOU WILL GET FORM DATA IN CONTROLLER? ( MVC INTERVIEW QUESTIONS WITH ANSWERS)

 

WHAT IS THE DIFFERENCE BETWEEN PRESENTER AND CONTROLLER IN MVC?(MVC INTERVIEW QUESTIONS WITH ANSWERS)

 

LEARN MVC (MODEL VIEW CONTROLLER) STEP BY STEP IN 7 DAYS – DAY 4

 

MVC Interview questions and answers PDF

 

MVC interview questions with answers

 

ActionResult vs. View() vs. ViewResult :- MVC interview questions with answers

Explain Areas in MVC?( MVC interview questions with answers)

 

Can you explain the purpose of ViewModel in MVC?( ASP.NET MVC Interview questions with answers)

ASP.NET MVC interview questions: - What are Filters in MVC?

What are areas in MVC?( MVC Interview questions with answers)

Explain the concept of View Model in MVC? 

Exception Handling in MVC

Explain MVC application life cycle?

100 MVC Interview question PDF download released , Enjoy

How can we use two (multiple) models with a single view?(MVC Interview questions)

MVC HTML.Form vs Ajax.Form – MVC interview questions with answers

Learn Microsoft Business intelligence step by step – Day 1

Can you create TempBag just like ViewBag?( MVC Interview questions)

MVC Unit Testing Unleashed

MVC and .NET learning tutorials for components of MVC and how do you perform unit testing in MVC?

Explain MVC model binders ? ( ASP.NET MVC interview questions)

Explain the difference between layout and master pages ? (MVC Razor interview questions) 


ENTITY FRAMEWORK INTERVIEW QUESTIONS ARTICLE


Windows Workflow Foundation(WWF) interview questions with answers Article

XML Interview Questions With Answers Article


Explain XML,DTD and XSL?(XML interview questions with answers)

HTML 5 Interview questions With Answers Article

HTML 5 interview questions with answers for LocalStorage and SessionStorage

 

How is the page structure of HTML 5 different from HTML 4?( HTML 5 Interview questions with answers)

 

What is datalist in HTML 5 ( ASP.NET HTML interview questions)?

 

What are the different new form element types in HTML 5?( ASP.NET HTML 5 interview questions with answers)

 

What is output element in HTML 5?( ASP.NET HTML 5 interview questions)

 

What is the difference between Canvas and SVG graphics?(ASP.NET HTML 5 interview questions with answers)

 

ASP.NET HTML 5 interview questions on SVG and Canvas

ASP.NET HTML5 interview questions with answers

What are web workers and why do we need them ?( ASP.NET HTML interview questions with answers)

 

Why do we need HTML 5 server-sent events? (ASP.NET HTML interview questions)

How can we add and remove data from local storage?(ASP.NET HTML 5 interview questions)

What is local storage concept in HTML 5? ( ASP.NET HTML 5 interview questions)

What is the difference between local storage and cookies? ( ASP.NET HTML 5 interview questions)

What is WebSQL?( ASP.Net HTML 5 interview questions)

 

What is session storage and how can you create one?( ASP.Net HTML 5 interview questions with answers)

 

What is application cache in HTML5?( ASP.NET HTML 5 interview questions with answers)

ASP.NET HTML 5 Application cache interview questions with answers

 

Explain the term cascading in style sheet ? ( CSS Interview questions)

What is difference between DIV vs SPAN in HTML ?( ASP.Net Interview questions)

HTML 5 Canvas Interview questions: - Canvas in HTML 5.

QuestPond’s interview questions and answers on HTML 5

 

Learn HTML 5 in 3 days – Day 1

 

 

 

Dotnetspider Questions And Answers Article

 

 

What is downcasting and upcasting ? ( .NET interview questions with videos)

 

What is the difference between String vs string? ( C# interview questions) ?

 

 

JAVASCRIPT INTERVIEW QUESTIONS WITH ANSWERS ARTICLE

 


3 IMPORTANT JAVASCRIPT IMPORTANT INTERVIEW QUESTION WITH ANSWERS