.net Interview Questions and Answers

.NET basics	Key words
IL code	Partially compiled
JIT(just in time)	IL code to machine language
Why is ithalf compiled ?	So that at run time we can detect the machine configuration , operating system give out optimized machine compiled code.
CLR	Heart of the engine , GC , compilation , CAS(Code access security) , CV ( Code verification)
CTS	Common data type for different .net languages so that integration is seamless
CLS	Sepcification of the IL code
CAS	It helps assign the .NET code permission of what they are capable of doing.
What  has happed for CAS .NET 4.0 ?
How does the .NET code compile ?	write  the code (c#,vb.net,c++.net)-- compiles to  a IL code -- CLR gives it to JIT -- JIT compiles to the machine specific language
Managed code	x`
Assembly	Its  a unit deployment ( EXE , DLL)
DLL and EXE	EXE - Self starting , DLL - You have to link
Manifest	it describes more about the assembly ( Meta data):-Versioning, References , dependent objects , Security , Scope
how do you do versioning	Assemblyinfo.cs / right click properties -- assembly information
What are strongly typed and weakly typed references ?	They help you to identify the publisher. Strong typed means we identify the DLL with a public key token while weak references are just simple references and identified only by class names
What is DLL Hell ?	versioning done here
what is ref and out ?
Strong names	They ensure that the class name is unique  to avoid confusion
Delay signgin	This is meant to protect DLL identity from your internal team developers , public key is give to the developer byextracting using SN.EXE -p , when you ready to go for  production you will onject the private key in the DLL SN.EXE -R
sn.exe
Value and Reference types	Values types int , double , bool etc , Reference types objects and strings. Value types are allocated on stack and reference types are allocated on heap. Value types are stored on different memory locations while reference types point to the same memory location
Stack , heap	They are memry types .Stack has value types , heap has reference types
boxing , unboxing	Box - Convert from value to reference , unboxing - reference type to value
Does unboxing and boxing bring down performance ?	yes they do bring down performance because data has to jump between heap and stack memory types.
How can we avoid Boxing and unboxing ?	You can not avoid it just minimize it
Garbage collector	Managed Unused objects will be cleaned by this mechanism. As a best practice you do not write any clean up code for managed unused objects.
How does the GC run	Its run in background
Does garbage collector clean unmanaged code ?	No
Do I need to write clean up code for managed objects ?	No, GC is smart to figure out unused objects and clean them up
So what do I do for unmanaged ?	You need to write the cleanup in destructor
What kind of problems do we have with destructors from GC pewrspecticve ?	lot of objects created in gen1
What are gen0 ,1 and 2?	Age of the objects.Gen 0 has newly created objects , gen 1 has objects which are bit older  , while gen 2  has objects which is more older than gen 1.This is for GC optimization , garbage collector checks Gen 0 frequently rather than Gen 1 and Gen 2.
Finalize a.k.a destructor	It’s a desctructor for cleaning up unmanaged objects.Decreases performance because of  objects move more to Generation 1. The time GC sees a destructor in a class it moves them to Gen 1
how to ensure that lot of objects are not created in Gen 1 with class having destructor ?	Implement Idisposable -- Expose a Dispose function -- Call GC.SuppressFinalize
What is Dispose function ?	Its  method exposed for clean up for client,Idisposable , Dispose , GC.SuppressFinalize
Finalize and Dispose	Finalize is a destructor and dispose is function which is implemented via Idisposable.Finalize is nondeterministic since we dont call it. It is up to the GC to call it. However dispose gives more control to the developer to perform cleanup. Since we can call it explicitly.
can we force garbage collector	Yes , GC.Collect
What are namespaces ?	They help us to logically group classes.
OOP
Why do we need  object oriented programming ?	1.No thinking in terms of real world 2. Reusability 3. Extensibility  4 Simplicity and maintainability
Important principles	APIE (OOPs ( Encapsulation , inheritance , Polymorohish and Abstraction))
How is the reusability problem solved in OOPs ?	Its solved by using classes and creating objects wherever necessary
What is a class and what is aobject	Class -> Blue print , template , Objects -> Bring life in Class , they make them live	Create a simple windows screen , which has supplier name , supplier code , supplier date , button calculate payment date , supplier date + 1 month
Encapsulation	Hide the complexity and make your object simple for external world.
How do we implement encapsulation	Encapsulation is implemented by using access modifiers
Can namespace span across DLL	yes , namespace are logical grouping of classes they can span
Abstraction	Show only what  is necessary and its more a thought process and abstraction is implemented by encapsulation
Abstraction and Abstract classes	Abstraction is OOPs concept and Abstract classes is half defined classes
difference  between Abstraction and Encapsulation	Abtsraction complement Encapsulation , Encapsulation implements abstraction
Private , public , protected etc	Private - Only with in Class , Public - Seen everywhere , Protected - With in same class and inherited classes , Internal - Within same class and same project and Protected internal is combination of protected + internal i.e. with in same class , iherited class and same project file.
What are constructor and desctructor ?	Constructor(same name as class name with no return type) - initialization purpose , while destructor(~) is for cleaning purpose.
Inheritance parent child which constructor fires first	Parent Constructor fires first and then child.
What is multiple interfaces are implemented	It will qualify with interface name
How to prevent inheriting futher	use the sealed keyword
What is Static classes ?	Static object has ony instance of the object created through out your application.
How to prevent object creation	Create the constructor as private
Where do we use the same ?	In Singleton pattern
Inheritance(:)	Depicts parent child relationship between classes
Polymprphism	objects will act different in differently under different situation
Method overloading	You can have same method name with different  number / types of parameters and depending on different parameters and types the appropriate functions will be invoked.
What are the different ways of overloading	types , order , ref m out … do it
What is virtual  and override keyword ?	Virtual keyword gives permission to its child classes to override the function / method. The child classes will then use the override keyword to override the same.
Whats the difference between overloading and overriding ?	Overloading we have same method / function names with different signatures ( input types) while overriding is a child parent concept where we override functionalities of the parent class.
Dynamic polymorphism	Method  overriding  and Virtual. You point your parent class object to child class objects to fire the necessary implementation on runtime. Even interfaces can be used to implement dynamic polymorphism
Static Ploymorphism	Method Overloading , we call same method with different input parameters
What is a interface	Its looks like a class but has no implementation. It has only empty definition of methods , functions, events , indexer.
What is the use of interface ?	to Establish a standard contract/standardization  ,   to decouple classes, dynamic polymorphism( runtime bhevior) ,version , multiple inheritance
Point to be remembered for interfaces	Interface keyword is used to define interfaces. Interface can not have field variables. Interfaces can not have implemented functions and methods. All methods in a interface in child class needs to be implemented. Interface can be used to implement run time polymorphism. You can implement multiple interfaces. All interface methods are public
can we define public , private acess modifiers in interface ?	No , by default everything is public.
Do child classes need to implement all the methods of a interface ?	Yes
Can we create a object of interface or abstract class	No
Abstract and virtual	Abstract no implementation and virtual has implementation
Multiple constructor with parameters
what is a abstract class ?	Half defined parent class   / base class  and child classes provide concrete implementation, like a generalization and specialization
What are abstract method and non-abstract method ?	Abstract method will not have any implementation while non-abstract methd will have implementation they are normal .NET methods
Point to be remembered for Abstract classes	An abstract class cannot be a sealed class. An abstract method cannot be private. You can have protected and internal if you want to. The access modifier of the abstract  method should be same in both the abstract class and its derived class. If you declare an abstract method as protected, it should be protected in its derived class. Otherwise, the compiler will raise an error. An abstract method cannot have the modifier virtual. Because an abstract method is implicitly virtual. An abstract member cannot be static.
Abstract classes and interfaces	Interface is a contract / standardization while abstract class is a half defined class for increasing reusability. Interface is forced implementation while abstract class is reusability via inheritance.
Can we have static methods in Abstract class ?	Yes
I have a interface IMyInterface which is implemented by class1 and class2 , I want to add some more functions and methods to the interface , what should I do ?	Create a new interface with additional methods or inherits from the interface and create a interface with methods and apply them. This ensure that the current contracts do not get disrupted.
Multiple code level inheritance
versioning
operator overloading	Operator overloading is a concept of plymorphism where you can redefine operators like + , - , * etc with additional functionalitiues. For instance we can redefine the + functionalities to add obejcts like obj1 + obj2.
Delegates	It’s a abstract strong typed pointer to a function
create and invoke a delegate	Declare , Create , point and invoke.
Use of delegate	Delegate refers via pointers so in case new methods are added or methods name changed we do not need to change at lot of places , dynamic calling of methods on run time. Its also strongly typed. Second - asynch calling and call back of methods
Delegate and interfaces	Delegate is at method level while interfaces are  at class and object level.
Multicast delegate(+= , -=)	It helps them to point to multiple functions and execute them sequentially.
Use of Multicast delegate	For boardcasting to multiple classes
What is Unicast ?	When one delegate point to one function its called as unicast.
Events	Events encapsulates(hides) delegates. They are useful for boradcasting , publisher and subscriber
Difference between delegates and events	Events use delegates internally. Delegates are pointer to function while events encapsulates ( hiudes) delegate function. In event clients can only subscribe while in delegates the client can subscribe as well as call all the functions of the delegates.
Asynchronous delegates	Begininvoke and endinvoke , calls the methods of delegates asynch , for parallel execution.
covariance and contravariance(.net 4.0)	This helps to point delegates in a very generic fashion
Shadowing	It replaces the complete element of the parent class. Like method becomes a variable
Shadowing and overriding	in shadowing the complete elements is replaced and in overriding you only replace the implementaton while the type remains same.
Shadowing practice	Should avoid Shadowing as far as possible.
Property indexer
1.1 collection differences
Difference between Array and Arraylist	Array - Fixed , ArrayList - resizable , Array has performance improve ment as no boxing and unboxing takes place while in array list it does , Arraylist can not store mutiple data types while array has fixed data types
What is a generic list	Strognyl typed list and improves performance by avoiding boxing and unboxing
Generic confined the type	public class cls<T> where T : String
Hashtable	Stores the value as hashed key , good for comparison , but bad in terms inserting valies
Stacks and Queues	First in first out and last in first out
Are there any performance problems with normal .NET collection ?	yes boxing unboxing happens
Regex and validation	Regex is nothing pattern matching and then validating the data using the pattern
GAC	To share the assembly across multiple  application in the same computer (C:\WINDOWS\assembly)
how do we register in GAC ?	Give strong name to DLL by click on the signing tab -- second you use thr GACUTIL -I to register the assembly in GAC
If you have different versions ?	Use Bindingredirect , Oldversion and newversion
satellite assembly	It’s a  compiled DLL which has images , text files any resource files. In other words no can tamper with your images , text files , icons etc.
Delay signing
Generics	Its to increase reusability by seperating logic and data type and its strong typed.
What are generic collections / Where have you used generics	Generic collections enable simple .NET collections to be generic enabled. So a normall List can be attached with any data type and we can avoid casting
Does generic improve performance	Yes , type casting is avoided
Threading	Threading is used to do pararellel execution.
How do we use threading	Create the thread object , pass the method name using thread start and call the start function.
can we set thread priority	ThreadPriority
threading can we stop and suspend	yes by using thread.start , suspend , stop
Background and foreground thread
readonly and constant
What is reflection ?	BY using System.reflection you can read meta data like properties , methods and also if needed you can invoked the methods and functions dynamically.
In what scenarios we would use reflection ?	technological tools like VS IDE , code reviews tools like Fxcop  , unit testing NUNIT etc
hod o you do reflection	Import system.rflection , get the type of t he object using gettype and then you can browser through functio an dproperties , to invoke use the invokemember
What is Serialization ?	Helps  to store in memory object in file and dessrialization means read the value from file and bring it in memory back.
ASP.NET and Webservices
Objects in ASP.NET	request , response , context , session and application
Autoeventwireup
Autoeventwireup	When the request is send  to the server from a UI element like button , drop down etc the postback happens
IIS , PORTS and Website
Application pool concept
HttpHandler and httpModules	They are means by which you can inject  pre/post-processing logic before the request reaches the page /gif/html
HttpHandler	HttpHandler is extension based processor.
.ASHX	Its nothing but Httphandler below , they helps us to display data which does need asp.net pages and thus they improve performance
HttpModule	HttpModule is a event based processor
Create a HttpModule	Create a class ,implement IhttpModule, attach events with your methods and register the class in web.config in httpmodule tag
Create a HttpHandler	Create a class implement IhttpHandler  , define implementation for processrequest,  register the class in web.config with file extensions in httphandler tag
ASP.NET application and page life cycle	environment created(request , response , context) - http module event ( begin request etc) - httphandlers ( page extensions) - page event (S/ILVER)-http module (end request)
What logic should be written in what events ?	init (add controls dynamically), load(write logic),validate(fire your valdation),event(ui element events),pre-render(changes before HTML is generated) , render ( changes before HTML is sent to the browser) and Unload ( clean up)
What is the difference between render and pre-render ?	Pre-render event happens just before the HTML is generated while render event happens when the HTML is sent to the browser.
What is a ISAPI ?
UI controls ( buttong , text box , drop down ..
why do you need Session ?	HTTP is a statless protocol and in order to remember states during postback we need session variables
how do we do Session management in ASP.NET ?	inproc (session object), outproc ( sql server and state server)
how do we implement Inproc session management in Asp.Net ?	by using session object of ASP.NET
Are session variables are local to a user ?	Yes
What is a viewstate ?	Its meant for session management and it uses hidden fields internally.Viewstate is a way to manage session using client browser , it uses hidden fields internally.
What is difference between viewstate and session variables ?	Viewstate value is accessed only in the current page while session variables can be accessed in different pages also.
What are the problems with viewstate	Securuity
What is web farm ?	Many times our current load demand increases. We can then create Web farm  which has two or more servers to meet the load.On the front end there is load balancer who routes the load to the appropriate server on load basis.
What is a loadbalancer?	Loadbalancer helps to decide which server the request should be routed. There are many load balancers one of the is Windows NLB ( network load balancer) in windows  server
What is web garden ?	You would like your IIS processes to run on different processors of the machine rather than loading only one processor.
How to implement web garden ?	In the process model tag ( web.config  or machine.config) provide the CPU mask value in decimal quivalent of the binary.
Why do we need a outproc session ?	Outproc sessions are needed in web farm environment
How can we do out proc session	step 1 - create session tables using ASPNET_REGSQL , Step 2 : Set <sessionState mode="SQLServer"  with connectionstring point to the database where session tables where created.
What are server side session management and client side  management ?
Whats the life of session ?	Session time out or when the user closes the browser
state server	aware used for outproc session
How can we cache a ASP.NET page ?	By using the <%@ OutputCache Duration="20" Location="Client"  VaryByParam="*" %>
What are the various ways by which you can cache your page ?	Param , Headers , Custom and UserControl.
How can we cache the whole page and  sections of the page should be dynamic ?	By using ASP:Substituion ( post cache substituion)
Cache whole opage	outputcache directive at page level
Whole page dynamic and sections of the page is cached	Outputcache directive at usercontrol levele.
Whole page achced and sections of the page is dynamic	Substituion control.
How can we cache as per location	location = server , downstream , client
What is a Application and Cache object ?	They help to create global objects in Asp.Net application.
What is the difference between cache and application object ?	In cache we can define dependency while application objects we can not define depedency.
What is cache dependency ?	you can define 3 kins of dependency file , time and key. If these dependencies change then the cache object becomes null.
If cache dependencies changes does it reload the depedency ?	No Cachdepedency does not have automation , we need to write t he code of refresh and reload.
Absolute and sliding
what is scavenging ?
Postback	When your user control sends data to the server postback event happens
Autopostback	When you want to send data to server as soon as the value changes in the control. It’s a simple property which we need set on the control.
Ispostback	It’s a page property tpo check if the postback has happened or not
Configuration setting in web.config	in the appsettings
Server.transfer and response.redirect	response.redirect has a double trip while server transfer transfers control from the server itself. Using response.redirect you can redirect cross domains while server transfer you can redirect only between pages of the same domain.	Create a simple project with page1.aspx and page2.aspx , create a simple buttong and in the button click redirect from page1.aspx to page2.aspx in the button click event
Authentication	Who the user is?
Authorization	What rights does the user has ?
How do you know the user logged in to ASP.NET system ?	using principal and identity objects which belongs to System.Security namespace.
What are different ways of authentication and authorization	Windows , Forms and Passport
What is  Forms Authentication ?	It’s a ticket based authentication . Tickets are passed via URL or stored in cookie file at the user browser.
What does actually a ticket mean ?	Ticket is a identification saying that you are a valid user. By using ticket you do not need to send userid and password again and again. Userid and password are sent first time , ticket is generated and later this ticket identifies your security role and rights.
What is windows authentication ?	In this the users are validated from windows local users and groups.
What is passport authentication ?	In this the users are validated from microsoft sites like hotmail , devhood , MSN etc , ticket is generated and that ticket can be used to do authentication . Autho in your web application.
how can we implement Windows authentication ?	Create users in yours windows user group -- in web.config file define <authentication mode="Windows"/> -- <deny users="?"/> Deny anonymous users -  map page name and roles.
How can we do Forms Authentication ?	Authentication mode = forms  in web.config file ,FormsAuthentication.RedirectFromLoginPage/Authenticate
what if cookies are diabled in forms authentication ?	Its passed via browser URL.
Single sign on	Single sign on is a concept where you login to one website and it automatically authorizes and authenticates other websites.
How can we implement Single sign on ?	Create a machine valudation key using (using RNGCryptoServiceProvider) - define the  same machine validation key in to the web.config file for all websites which will be coming in the single sign on -- use forms authentications
aspnet membership and roles	It helps to expedite your development for authentication and authorization by giving ready made user and roles tables , user interfaces and API to connect to those tables.
how does ASP.Net membership roles work ?.	run aspnet_regsql -- do web.config configuration ( connectionstring , providers and roles) -- call the API from your ASP.NET behind code (Membership.CreateUser,Roles.CreateRole and Membership.ValidateUser)
Debugging and Tracing in ASP.NET	Tracing is a way to monitor the execution of your ASP.NET application. You can record exception details and program flow in a way that doesn't affect the program's output.	dev
how can we do tracing in ASP.NET pages	Trace=true	dev
whats the problem with trace=true	our debugging is shown to the end users , so we need to use tracelisteners	dev
How can we configure tracelisteners and source ?	In web.config file define your source and listeners , in your code create the trac object and start sending messages(trace.write)	dev
What is the namespace ?	It logically groups calsses together
Ajax	Ajax is a technology by which you can do asynhcrounous processing and only the ncessary values are posted rather than posting the whole page. Performance and great user experience.
What is updatpanel	Updatepanel is a component which ensures that your server objects become Ajax enabled.It logicall groups them so that only that data is posted.
What is Script manager proxy ?	In Ajax we can have only one scropt manager. But there are condition like master  pages where we would need two script manager
Enablepartial rendering	This enables asynchrounous processing
How can we consume webservices in Ajax ?	In Script manager proxy  give asp:servicereference and give ASMX path and use javascript to call the objects
What is Jquery ?	Jquery is javascript library to make your javascript development simpler.
Difference between datagrid , datalist and repeater	Datagrid displays everything as table , datalist has tables but gives flxibility like number of columns to displayed , while repeates is highly customizable, performance goes first repeater , then list and finally grid
Gridview and datagrid	Gridview is the sucessor of datagrid,Automatic handling of sorting, paging, updates, and deletes,Additional column types and design-time column operations, rich design capaibilities
Paging in datagrid
SQL Server
Database and Tables
SQL
self/equi joins
Referentrial integrity
Normalization	It’s a database design technique to avoid repetitive data.
Normalization	3 normal form , 1st normal form Break is Smallest unit , 2nd normal form any repetitive data should be moved to a separate table and forigen key , 3rd normal form Any non key field should not depend on other non key fields of the table
Denormalization	Its combining multiple table data in one table thus avoiding joins for performance imporvement ex - reporting applications
When should we use normaliztion and denorm	Normalization ( integrity , avoide redudant) and denorm ( faster treival , reporting etc)
Indexes	Indexes helps to make your search faster by using balance tree( B tree) concept
Balance tree	It’s a tree structure with leaf nodes having actual data , non leaf node and root node. So rather than browsing through records sequentially it zeroe's on range of records , this making your search faster
Clustered indexes	The leaf node points to actual data
Non-Clustered indexes	Leaf node points to a pointer and that pointer points to actual data
When will use a clustered index and not clustered index ?	You will choose fields with unique values as clustered indexes while fileds which participate in search criterias you will select them as non-clustered indexes.
Self join
inner join
left jon
right join
cartesian
case statements
Select all rows from both tables	SELECT     * FROM         Customer INNER JOIN                       CustomerPaid ON Customer.Id = CustomerPaid.Id union SELECT     * FROM         Customer left JOIN                       CustomerPaid ON Customer.Id = CustomerPaid.Id union SELECT     * FROM         Customer right JOIN                       CustomerPaid ON Customer.Id = CustomerPaid.Id
in group by if we put a column which is not in group what wuill happen	Query will no fire
cross join / cartesian
Stored procedures	Stored procedures are SQL Server objects which have one or many SQL statements
What is advantage of SP over inline SQL	They are precompiled and thus increases perforance ( parsing , plan and then execution)
What are triggers  ?	Trigers are logic which you want to execute insert , delete and update operation on a table
What are types of triggers ?	After trigger ( fires after the operation )and instead of trigger ( before the operation). Operation means insert , update delete
What are inserted and deleted ?
Functions	It returns a scalar value and is called from stored procedure	declare @count1 int set @count1= dbo.getfunctioncount() print(@count1)
Difference between function and stored procedure	Function reduce redudant code in SP.Function - You can not change data while in stored procedures you can , can return only one value while  SP returns multiple values, functions can be called inside a SP but not the vice veras
How to handle errors in Stored procedures	using Raiserror function , give message severity and state
Paramters in Stored procedure	input , ouput , return( only one)
profiler	It’s a simple listerner tool which tracks what kind of SQL statements are fired on your SQL server and using it you can do debugging and improve performance depending on the trace file
optimzation	Create indexes ( balance tree), SQL Plan ( Table scan or Index scan) , SQL profiler  and Data tuning advisor for getting suggestion of indexes
sql plan	Describes how your SQL statements will execute.
sql server  locking	set isolation level read committed etc etc in stored procedure
SQl injection	It is a Form of attack on a database-driven Web site in which the attacker executes unauthorized SQL commands by taking advantage of insecure code on a system.
How can you avoid SQL injection	use stored procedures and avoid on the fly SQL concatenation.
SSIS	SSIS helps us to do ETL ( Extraction - Transformation and Loading). We need to create a Business intelligence project define source , transformation and destination and run the DTS package.
SSRS
SSAS
Difference between delete and truncate ?
ADO.NET
What are ADO.NET components ?	Connection , Command , Dataset , dataadapter , datareader(2C and 3D)
Whats the difference between Dataset and datareader ?	Dataset(back and forth) - works disconnectly , CRUD , reader works connecteldy
In what scenarios we will use a dataset and datareader ?	Dataset :- When you want to take group of records , modify/browse in offline mode( move back and forth)  and then send the whole changes online. Datareader :- You have huge number of records and you want browse in the forward onnly direction
How do you connect to ADO.NET	connection , Command , ExecuteNonQuery/ExecuteQuery , use it and close it
how do you load a dataset	connection , Command , Dataadapter , load dataset by Fill method , use it and close it
Dataview	Helps to search, sort filter dataset
Command object methods	Executereader , executenonquery and executescalar
how can we use stored procedure in ADO.Net	ObjCommand.Commandtype = CommandType.Storedprocedure , give the stored procedure name
Wht connection.close	To ensure the SQL Server resources are released
How do you write and read using XML using ADO.Net	readXML , WriteXML function  of dataset object
Problems of Locking	Dirty Reads,Unrepeatable reads,Phantom reads and Lost updates
optimistic and pessimistic	Pessimistic means locks are acquired when the record is fetched until the updation and optimisitic means locking is acquired when the data is updated
how can we do optismistic locking in ADO.Net ?	dataset and dataadapter  by default supports optimistic locking , timestamp,checking  old values and new values
Pessimistic locking	Read committed( reads data which is committed) , Read uncommitted ( reads data which is yet not committed), repetable read ( No updates allowed)and Serializable (Exclusive lock no updates , insert and selects).
Scnearios of pessimistic and optimistic	Transactional screens / data enty screen where large number of users,critical batch processes done at the end of the day or year( closing of accounts).
What is a transaction ?	When you have group of statements . Process doing insert update and delete , you would want either all of them pass or either all of them fail.
how can we implement trans	call begintransaction in connection object , committransaction or rollback, in stored procedure begin tran tr1 and commit tr1
Connection pooling	Reuse the connection object rather than reusing from scratch.In connection string specify pooling=true
	dataset is  collection of tables with relationship and recordset has only tables
How do you pass parameters t stored procedures	Paramater collection of command object
how can you automatically fill command object	Command builder.
Datarelation
nerge
Reporting
Where do you get Crystal reports ?	It’s free available in VS
How did you create report using crystal reports	used RPT file -- Define my data sources -- Finally uses the reportviewer to display the RPT file  on the UI.
how to provide inputs to crystal report	By parameter field
Remoting , Webservices and WCF
What is Appdomain ?	Appdomains make logical boundary / isolation  inside a process. Process -- Appdomains(task and application).
What's the advantage of Appdomain ?	If one Appdomain crashes the other Appdomain or the whole process is not closed / terminated.
What is the use of remoting ?	It helps to make remote method calls to objects which are residing in different appdomain. These Appdomain can be located in a different geographical location or different networks.
How do you create a remoting object ?	Create a interface -- Implement the object by creating MarshalbyRef -- Host your server object using Remoting"RegisterWellKnownServiceType" -- Create the client to call the service"Activator.GetObject".
Problems with remoting	Client and server can be only in .NET language , complicated, Faster than other remoting technologies, pick and choose Channel and formatter ( customization)
Comparison of DCOM and remoting
remoting objects life time
what is a webservice ?	Webservice is a technology by which you can expose your business functionality on HTTP using SOAP XML format.
How can we do webservice security	specify windows , passport , forms and pass credentials through the client proxy object
UDDI and DISCO	Helps to search and discover your webserbvice from the UDDI directory
What is WSDL ?	It’s a meta data which shows what are the methods , properties , datatypes exposed by a service
What is SOAP ?	It’s a XML protocol which is defined how your service and client communicate.
What is difference between Webservice and Remoting	Webservice(Cross language , only Http) , Remoting ( only .NET platform , Any protocol)
What is  Service Oriented Archotecture ?	SOA is nothing but desigining your system in self contained services which communicate via standard messages thus making your services loosely coupled. Services -- Self contained , Orchestrate , Industry Standard messages , Reliable , Aynshcrounous message , Cross plat form  describe and discover
Why WCF ?	It was to satisfy  SOA principles of WS-* specification.
What is WCF ?	WCF = Webservices + remoting + COM plus + MSMQ
What is Address binding Contract ?	Address - where is it hosted , Binding - how is the protocol , Contract - what  is the interfcae
What is  Service contract , Operation contract and Data contract ?	Service contract - Service  name , Operation contract - Your methods and functions , data contract - Custom data type , data member - property and functions of your data contract
namespace of WCF	System.ServiceModel
what's the difference between WCF and Webservices ?	Webservices = WCF - ( remoting( multiple protocols) + COM plus ( transactions) + MSMQ(queueing))
What are the different hosting mechanisms of WCf services ?	IIS , Self hosting or WAS server
how do host in IIS ?	By suing the SVC file we can host our service  on IIS
How do you do self hosting ?	Create object of Service host , provide Address ( Uri) , Binding ( Wshttpbinding) , Contract ( Interface) and open the host.
When should we go for Self hosting and when to go for IIS	Http go for IIS ( we getready made features like always running , process recycling,security,ssl etc), For other protocols go for self hosting
What are the important bindings/	BasicHttp ( Like webservice plain text) , WsHttp ( Like basic with encryption) , TcpBinding ( To use TCP protocol for services ) , NetNamesPipe ( With in the same machine ) , MSMQ ( WCF integration with Queuing mechanism)
BasichttpBinding and WshttpBinding	basic is plain text while Wshtpp is encrypted
How to secure basichtppbinding	use SSL on webservices
Ho can we do debugging and tracing in WCF	In Web.config <system.diagnostics> specify  WCF trace source objects like System.ServiceModel , message logging etc. , then use the Svtraceviewer tool to see the mesagges
How can we do transaction in WCF ?	1 . Operation contract define TransactionFlow , 2. In Web.config file make your Binding as transaction flow as true 3. In client side call the services in one transaction scope with rollback and committ.
WCF Security	Transport , message and transport + message
WCF Transport	SSL , Specify in config file https in address tage ,  Specify security mode and install SSL in your WCF services
WCF overloading is it allowed	[ServiceContract] interface ICalculator {  [OperationContract(Name="AddIntegers")]  int Add(int a,int b)  [OperationContract(Name="AddDouble")]  double Add(double a,double b) }
Dynamic polymorphism
WCF Duplex
WCF message
WCF Instancing	Per call , persesion and single instance
WCF concurrency	Single , Multiple , Rentrant
WCF REST	Helps  to expose your WCF service via simple HTTP get and post
WCF integration
LINQ and EF 4.0
What is LINQ	It’s a OR mapper  technology ,2 important use 1 - BO , DAL and Mapping , 2 - General Queries which can fired on any data store.
What is a Entity class	It’s a Business object which has mapping with the data store.
What is data context	It’s the data connection layer to load the entity object with data
How do we declare 1 to  many and 1 to 1 relation	Entity set for 1 to many and entity ref for 1 to 1
LINQ to SQL
Optimization using data load options
CRUD example using LINQ	insertonsubit , deleteonsubmit , submitchanges
Call Stored procedures using LINQ	Using the function attribute
LINQ locking
PLINQ	PLINQ executes two linq queries parallely
LINQ transactions	By using the transaction object of data context class
DBML	Database markup language
WPF and Silverlight
GDI , GDI + and Directx
Simple WPF application	WPF is for creating windows application , the user interfaces can be represented using XAML and it uses directx internally.
Rendering in WPF application
Architecture of WPF
What is silverlight ?	It’s a plugin which runs inside the browser. It can run on cross platform and cross browser.
Architecture of Silverlight
Animation fundamentals in Silverlight
What are different way of silverligjt layoutin..	Stack panel ( one above another ),Canvas ( we specify left and top), Grid ( If you want layouting using table structure , rows and columns)
What are the different ways of binding the silverlight UI with .Net classes and objects ?	One way ( UI to BO), two way( UI <-> BO) and one time( BO to UI).
In what scenarios you will use what ?	One time binding - reports , Transaction screens two way , Pure input screen one way.
How can we connect froom Silverlight to SQL Server	By using WCF services.
Why not directly ?	Because silverlight is a plugin which is a downsized version .NET framework and it does not have system.data
Consume WCF service in Silverlight	WCF service should have client access policy and cross domain , from silverlight you need to call the data asynchrounously
Database operations using Silverlight	You can not call System.data directly from silverlight , so you need to call the WCF service and WCF service will do the necessary data operations
Prism
MVVM
WWF
WWF architecture
Composite and leaf activities
Sequential and State machine work flow
Simple example of WWF
State machine work flow
Design patterns
Which design pattern have yu used ?	So pick your best pattern corelate it with your project and speak about it.  Share global fdata
Design patterns	Design patterns are  tried and tested solutions for design problems in our project.
What are the categories of Design patterns	Creational , Structural and Bheviorial
Factory pattern©	Centralizes creation of object in a class and passing back a interface reference to the client. Main use is decoupling( UI - BO - DAL).(Creates an instance of several derived classes )
Abstract Factory Pattern	Abstract Factory groups Factory patterns.
Builder Pattern
Prototype Pattern
Where is prototype used ?	Audit trail , differences of objects , cancel and revert
Singleton Pattern	Helps to create one instance of the object.
How did you implement singleton pattern ?	Create a class with private constructor and define your object as static and expose it
We can achieve the same by cache and application	Its technology specifc and not a generalized solution
we can achieve the same by using static object
Adapter Pattern
Bridge Pattern
Composite Pattern
Decorator Pattern
Facade Patetrn
Flyweight Pattern
Proxy Pattern
Mediator Pattern
Memento Pattern
Interpreter Pattern
Iterator Pattern
COR Pattern
Command Pattren
State Pattern
Strategy Pattern
Observer Pattern
Template Pattern
Visitor Pattern
DIIOCConcept Pattern	DI helps to inject depedent objects in to a class. DI injection can be implemented by Unity app block / Windsor castle
What is MVC,MVP and MVVM	These are GUI architectural pattern with only one intention of seprating the UI Logic , state and synchronization in to a separate class.
How is MVP	Hit come to UI first , from there he calls presenter clas , presenter call the model and present then send updates via a interface to the UI. UI --> I --> P - M
Model view controlle	Sepearetes Action , View and Data by using controller class. We have template MVC template which helps to automate the same. In odld asp.net we will httphandler which was tedious
MVP and MVC	First hit to the UI , First hit to the controller/MVP presenter takes care of logic , controller takes care of logic as well as statmanagement
When to use these patterns	If you have complicated UI code , MVC is mostly used for ASP.NET , MVVM is used for Silvetrlight and WPF becaiuse of rich command objects, MVP is not used currently because of less automation
UML	UML is a modelling language which helps us to document and design our software application.
Use Case Diagrams	Its helps us to document "What" of the system from user point of view.
What does use case have normally ?	Use cases are task having scenarios and Actor executing those scenarios
How did you document your requirement  ?	Step 1 :- We identified the task which where nothing but our use cases , Step 2 :- For every use case we wrote down main scenario / alternate scenario and actors responsible
What are primary actors and secondary actors ?	Primary actors are the users who are the active participants and they initiate the use case, while secondary actors are those who only passively participate in the use case.
In which format did you gather your uses cases	Company Template in word document
How did you show relationship n uses cases	By Extend and include
How did you translate your requirement to design ?	We has already gathered the requirement using  use cases and also relationships where between them  using the include and extend, we use these use cases and identified nouns ( classes) and verbs ( they became our methods and functions) , relation ship between classes where identified by extend and include of use cases. Later for complex scenario we use Sequence diagram / Collobaration. We also had a over all architecture diagram which depicted hardware , components and logical grouping by using Component , Deployment and package.
Class Digrams	Class diagrams shows the static structure of project. They  help us visualize the classes and relationships between them
How do you denote a class diagram in UML ?	Its denoted with square divided in to 3 section , top section has class name , middle section has properties and last section has operation / function / methods
How to demote public , private and protected in class diagram	(+)  Public , (-)Private  , (#) protected , internal
How do we define relationships in UML	by multiplicty (1-*)
What is composition and aggregation	Composition - life time of dependent objects are same , Aggregation :- Life time of dependent objects are not same and they can exist without each other. Composition is shown by filled diamond while aggregation is shown by empty diamond.
How can denote inheritance ?	Empty traingle arrow key.
How can we denote abstract classes and interfaces	{} - Abstract classes , <<>> - Interfaces
Object Diagrams
Sequence Digrams	Object diagrams over a period of time.
how did you draw a sequence diagram ?	The objects in rectangle on the top side -- message by arrows and object life time vertical rectangles.
How do you show synchronous and asynch messages	Synch by dark arrow and asynch by thin arrow key
Recursive message	By small rectangle in a big rectangle
Conditcion	Inside Square bracket
Message branching	By two rectangles with condition and branching arrows from the same.
Collaboration Diagrams	It shows the same information as sequence diagram but the emphsais is more on messages than life time of the objects
Activity Diagram	Activity diagrams depicts complex flow of a system
Parallel processing , partionting and conditions	Shows by dark bar , Swimlanes for partitioning , Diamond is for conditions
State chart Diagrams
Component Diagrams
Deployment Diagrams
Stereo Types Diagrams
Package Diagram
UML Project Flow
Functionpoints
Introduction
EI Fundamentals
EO Fundamentals
EQ Fundamentals
EIF Fundamentals
ILF Fundamentals
GSC Fundamentals
Productivity Factor
How did you reconcile
How did you accommodate SDLC
RUP
What is Agile	Agile is a principle which means accept changes
How did you do Agile	Used SCRUM
What are the principles in Agile	Accept changes , Interaction with customer , people , working code
What is Agile SCRUM ?	Scrum is a methodology to implement agile
How does SCRUM process work	Customer Prepare Product back log -- priortizes them -- development team breaks them in to sprint -- every srpint has daily stand up meet( Today , yesterday,problems) -- Every week retrospective -- After sprint give chance of changing
When Agile and Waterfall ?	Water fall - requirement is fixed , Agile -- If requirements will change or evolve.( Time to market)
How did you code review?	Mostly automation and the process
Role of your current project(SDlC)	I was involved in all phases of SDLC cycle.Requirement( use cases , activity) - Design(Class , ER diagrams , Sequence / Collboaration) -coding / unit testing (NUNIT)- SIT - UAT - go live(junior ( coding) helped out ,poc( proof of concept) , pm / archotect) - end to end.
simplicity your projects	The applicaton was a integrator between indian chemical companies and EICA to provide certifications for Indian chemical companies as per EICA standards	It’s a internal ATM management system in ASP.NET  which has various functionalities creating Contracts , Customer report , hand bills , Scheduling etc.
Can you explain  the architecture of your current project ?	It was a tiered architecture , UI / BO and DAL. With UI in ASPX pages , BO in normal .NET classes and data access layer helps to fire SQL queries on SQL Server. We had used singleton pattern and factory patterns in the project.
What  software process did you follow for your project ?	We followed normal SDLC model. In requirement we wrote the use cases , design we created classes and DB diagrams , finally we coded and unitested and went live.
How did you test your project ?
How did you do requirement for your project ?
technical Design
Acceptance
How did you do unit testing in .NET ?
Summary
Speak abt yourself
OOPs
.net basic
asp.net
Why Gap ?
Differences ( .NET , ASP.NET and SQL Server)
HLD and LLD	I do understand HLD but most of the times we have created a overall index of LLD and then expanded in to details. The use of HLD is mostly to verify before investing in LLD that are we in the right direction , to take approval from stake holders. HLD has 5 section Overall all architecture diagram ( Deployment , Component diagram , package diagram) Overall Road map ( 3 tier , MVC , MVP MVVM) technology Unit testing Load test startergy POC :- Proof of concept LLD Overall detail architecture diagram Class diagrams , Object diagrams , Sequence / Collaboration , DB design In depth test stratergy Psedu-code