Microsoft Interview Question Answer

Microsoft
What is the difference between temp table and table variable?
SYNTAX
Temporary Tables: CREATE table #T (…)
Table Variables: DECLARE @T table (…)
Table Variables are out of scope of the transaction mechanism.If you make changes to a Temp Table inside a Transaction and Rollback the Transaction those changes will be lost.Changes made to Table Variable inside a Transaction will remain even if you Rollback the Transaction
Any procedure with a temporary table cannot be pre-compiled An execution plan of procedures with table variables can be statically compiled in advance
Table Variables exist only in the same scope as variables.They are not visible in inner stored procedures and in exec(string) statements
Table variables are in-memory structures that may work from 2-100 times faster than temp tables.
Access to table variables gets slower as the volume of data they contain grows.
At some point, table variables will overflow the available memory and that kills the performance.
Use table variables only when their data content is guaranteed not to grow unpredictably; the breaking size is around several thousand records.
For larger data volumes, use temp tables with clustered indexes.
What is boxing and how it is done internally?
Boxing is an implicit conversion of a value type to the type object
int i = 123; // A value type
Object box = i // Boxing
In case of value type ,value is stored in the stack but after boxing process value is stored in to heap.
What is ODP.NET?
Orcle9i Data Provider for DotNet using this provider we can connect to Orcle DB.
About remoting and web services.Difference between them?
Remoting is a technology used to communicate between applications of same platform and encoding will be in the form of binary.
In the case of web service applications in different platforms can communicate and data will get transferred as xml files
What are the security issues if we send a query from the application?
Third party can able to see your query and also there can be SQL Injection if the query is SQL statement.
Query should be encrypted before sending from application.
Difference between Htttppost and Httpget Methods?
HTTP Get is a protocol is used to get the data from the server side.While coming to the HTTP post to append the data to the client side to server side which can given by the user on URL
what is caching?
Caching is one of the statemanagement technics as well as the optimization. It's small memory location at the server side that will retain the user data for the purpose of subsequent requessts.
what is managed and unmanaged code?
Managed code: A code that is managed by CLR is know as Manged code for example C#,j#,Vb.Net etc
Unmanged code: A code that is not managed by CLR is known as Unmanaged by unmanaged code. for example c++, java, c etc
Have u used webcontrols?Tell me something about these?
Yes, webcontrols are represented in the form of dll.they are compiled content and the controls will appear in the toolbox. cathing is not supported.
Can you store dataset in viewstate?
No, You cant directly store Dataset in ViewState. You can get XML from dataset store that Xml in ViewState. While getting From ViewState convert to xml and then from xml to dataset.
what is Disco?what it will do?
DISCO is the discovery file which gives path to the Webservices
It contains WSDL(Web Service Description Language)When one searches for the Web Services, it will go to the DISCO whcih gives actual info. about the particular Webservices
what is soap?
Soap is a formatting protocal.
When we send data to the webservice the data will be passed in network wire.That data has to formatted by SOAP. and sends to the service.
then the service will give response to that request.This data is also formatted by Soap and give it to the client.
SOAP--> HTTP + XML
The format is XML because it is platform dependent.this service is used by other applications.
can we call webservice in Html form?
yes we can call a webservice from html form.Your web page directory should include the 'webservice.htc'file. This file adds a behavior to html files for calling web services.
How can you assign styles to webforms?
by using cascading style sheets.
what is manifest?
Assembly manifest is a data structure which stores information about an assembly .The information includes version information, list of onstituent files etc.
How can you get public key information?
Using ILDASM-Intermediate Language Disassembler which will open the manifest of that particualar assembly.
what is generics?
Generics are the most powerful feature of C# 2.0. Generics allow you to define type-safe data structures, without committing to actual data types.
what are Httpmodule and HttpHandler?
http handler is a information between the web browser and web server
About Garbage Collector?
garbage collection is a form of automatic memory management.The garbage collector attempts to reclaim garbage or memory used by objects that will never be accessed or mutated again by the application.
Singleton Design pattern? How do you achieve it?
Singleton design pattern we can implement using Static key word that means only one instance.All the instances are coming from the same memory location.
what are webservices?In which circumstances we can go for
webservices?
Web service is a reusable component which resides in the web server.
It is language independant and platform independant. This means that any application written in any language can use the service of a web service. It uses the SOAP protocal and communicates using XML.
what are partial classes and their use?
“partial” keyword can be used to split a single class, interface, or struct into multiple, separate files in ASP.NET (using C# as the language). This permits multiple developers to works on these files, which can later be treated as a single unit by the compiler at the time of compilation and compiled into MSIL code.
Partial classes can improve code readability and maintainability by
providing a powerful way to extend the behavior of a class and attach
functionality to it.
The partial modifier can only appear immediately before the keywords
class, struct, or interface.
Nested partial types are allowed in partial-type definitions.
Using partial classes helps to split your class definition into
multiple physical files.
Note that the partial keyword applies to classes,structs, and
interfaces, but not enums
Difference between .NET components and COM components?
.net component.....>these dlls can be used by any application (platform independant)these components are resolved from dll hell problem
com components.......>platform dependent components
What is an application domain?
Application domain is something that isolates the application from interupting each other.
What are runtime hosts?
Runhosts is a special type where CLR is executed and managed.
How do you do validations. Whether client-side or server-side
validations are better?
Asp.Net has few validation control like compare,requirefield,range ,regulor-expression and custom
u can use any validation control with html ,asp control
Asp.net validation control are by default cilde side validation
and the client side validation is better bcoz it's reduse the burdon to the server.
Features in ASP.NET?
It has Comman Language Runtime execution Engine which translate the source code into Microsoft Intermediate Language (MSIL) .It is called Managed code.
Types of caching. How to implement caching?
there are 3 types of caches is there they are
1)page caching
2)page fragmentaion caching
3)data caching
in case of the page caching the total page will be cached for certain amount of time(i.e the time will declared by ourself)
and in case of page fragmentation caching only a part of the data will be cached for some amount of time
Data caching, which allows developers to programmatically retain arbitrary data across requests
Difference between .NET and previous version?
previous version is the com based which was does not support inheritance, it was object based and it is completley binary standed code.
.NET is the fully object oriented language.
Is overloading possible in web services?
Yes,its possible
Types of session management in ASP.NET?
There are two types of session management in ASP.NET namely, Client side and Server side.
Client side: Hidden forms, Hiddenfields,query strings,Cookies, View
state
Sever side: Application object, Session State, Caching.Each type has
its own advantages and preferences.
What is reflection and disadvantages of reflection?
Reflection is used for accessing assembly related information ie, methods ,properties etc we can dynamically invoke methods using reflection.reflection can use for latebinding of an object.
What is the difference between and ActiveX dll and control?
Activex dll is created any language and use in application.by using javascript .Activex dll use only as client side control.Control is created in same language of application and use as like drag and drop on page.you can use controls server side as well as client side.
What is custom control. What is the difference between custom control and user control?
Both the custom control and the user control will be developed by the user, the only difference is user control is application specific where are custom control can be used in any application. We can create a dll for the custom control and can place it in the toolbox where are for user control it's not possible it's just an .ascx file as .aspx.