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Interview Questions in ASP.NET, C#, VB.NET, SQL, .NET Framework

Nov 13, 2013
Here I am posting the interview questions whatever i have faced in my interviews
I have searched for so many websites and gathered information from my friends to answer the questions perfectly.

i think these questions are very helpful for the people who are trying to get the job on .NET
The most common question for experience persons is

Why would you like to change the company?

1) I am looking for a more challenging career in a firm with a larger employee base such as yours.
2) Keeping in mind my career goals, the time has come for me to move onto the next rung of 
the ladder and make a mark for myself. This can be achieved in a company like this.
3) It is just a career move to enhance my knowledge in my own area of interest.
After completion of this question only interview will go for further questions

Difference between stored procedure and function

1) Procedure can return zero or n values whereas function can return one value which is mandatory.
2) Procedures can have input, output parameters for it whereas functions can have only input parameters.
3) Procedure allows select as well as DML statement in it whereas function allows only select statement in it.
4) Functions can be called from procedure whereas procedures cannot be called from function.
5) Exception can be handled by try-catch block in a procedure whereas try-catch block cannot be used in a function.
6) We can go for transaction management in procedure whereas we can't go in function.
7) Procedures cannot be utilized in a select statement whereas function can be embedded in a select statement.

Difference between Abstract and Interface

Abstract Class:

-Abstract class provides a set of rules to implement next class
-Rules will be provided through abstract methods
-Abstract method does not contain any definition
-While inheriting abstract class all abstract methods must be override
-If a class contains at least one abstract method then it must be declared as an “Abstract Class”
-Abstract classes cannot be instantiated, but a reference cannot be created
-Reference depends on child class object’s memory
-Abstract classes are also called as “Partial abstract classes”
-Partial abstract class may contain functions with body and functions without body
-If a class contains all functions without body then it is called as “Fully Abstract Class” (Interface)

Interface:

-If a class contains all abstract methods then that class is known as “Interface”
-Interfaces support like multiple inheritance
-In interface all methods r public abstract by default
-Interfaces r implementable
-Interfaces cannot be instantiated, but a reference can be created

Index types in SQL Server

Clustered Index

Only 1 allowed per table physically rearranges the data in the table to confirm to the index constraints for use on columns that are frequently searched for ranges of data for use on columns with low selectivity.

Non-Clustered Index

Up to 249 allowed per table creates a separate list of key values with pointers to the location of the data in the data pages For use on columns that are searched for single values 

A clustered index is a special type of index that reorders the way records in the table are physically stored. Therefore table can have only one clustered index. The leaf nodes of a clustered index contain the data pages. A non-clustered index is a special type of index in which the logical order of the index does not match the physical stored order of the rows on disk. The leaf node of a non-clustered index does not consist of the data pages. Instead, the leaf nodes contain index rows.

Included Column Index (New in SQL Server 2005) 

In SQL Server 2005, the functionality of non-clustered indexes is extended by adding non-key columns to the leaf level of the non-clustered index. Non-key columns can help to create cover indexes. By including non-key columns, you can create non-clustered indexes that cover more queries. The Database Engine does not consider non-key columns when calculating the number of index key columns or index key size. Non-key columns can be included in non-clustered index to avoid exceeding the current index size limitations of a maximum of 16 key columns and a maximum index key size of 900 bytes. Another advantage is that using non-key column in index we can have index data types not allowed as index key columns generally.

In following example column Filename is varchar(400), which will increase the size of the index key bigger than it is allowed. If we still want to include in our cover index to gain performance we can do it by using the Keyword INCLUDE.

USE AdventureWorks
GO
CREATE INDEX IX_Document_Title
ON Production.Document (Title, Revision)
INCLUDE (FileName)

Non-key columns can be included only in non-clustered indexes. Columns can’t be defined in both the key column and they INCLUDE list. Column names can’t be repeated in the INCLUDE list. Non-key columns can be dropped from a table only after the non-key index is dropped first. For Included Column Index to exist there must be at least one key column defined with a maximum of 16 key columns and 1023 included columns.

Avoid adding unnecessary columns. Adding too many index columns, key or non-key as they will affect negatively on performance. Fewer index rows will fit on a page. This could create I/O increases and reduced cache efficiency. More disk space will be required to store the index. Index maintenance may increase the time that it takes to perform modifications, inserts, updates, or deletes, to the underlying table or indexed view.

Another example to test:

Create following Index on Database AdventureWorks in SQL SERVER 2005

USE AdventureWorks
GO
CREATE NONCLUSTERED INDEX IX_Address_PostalCode
ON Person.Address (PostalCode)
INCLUDE (AddressLine1, AddressLine2, City, StateProvinceID)
GO

Test the performance of following query before and after creating Index. The performance improvement is significant.
SELECT AddressLine1, AddressLine2, City, StateProvinceID, PostalCode
FROM Person.Address
WHERE PostalCode BETWEEN '98000'
AND '99999';
GO

Interview questions 

What are differences between Array list and Hash table?

Ans: 1) Hash table store data as name, value pair. While in array only value is store.
2) To access value from hash table, you need to pass name. While in array, to access value, you need to pass index number.
3) you can store different type of data in hash table, say int, string etc. while in array you can store only similar type of data.

What are differences between system.stringbuilder and system.string?

The main difference is system.string is immutable and system.stringbuilder is a mutable. Append keyword is used in string builder but not in system.string.
Immutable means once we created we cannot modified. Suppose if we want give new value to old value simply it will discarded the old value and it will create new instance in memory to hold the new value.

What are the differences between Application object and session object?

Ans: The session object is used to maintain the session of each user. If one user enter in to the application then they get session id if he leaves from the application then the session id is deleted. If they again enter in to the application they get different session id.
But for application object the id is maintained for whole application. 

What are the different types of indexes?

Ans: Two types of indexes are there one is clustered index and non-clustered index

How many types of memories are there in .net? 

Ans: Two types of memories are there in .net stack memory and heap memory

Is it possible to set the session out time manually? 

Ans: Yes we can set the session out time manually in web.config.

What are differences between function and stored procedure?

Ans:
1) Function returns only one value but procedure returns one or more than one value.
2) Function can be utilized in select statements but that is not possible in procedure.
3) Procedure can have an input and output parameters but function has only input parameters only.
4) Exceptions can be handled by try catch block in procedures but that is not possible in function.

What are the differences between Abstract and interface?

Ans:  

1) Abstract and interfaces cannot be instantiated but we can inherit.
2) Interface contain only declarations no definitions. Abstract contain declarations and definitions.
3) The class which contains only abstract methods is interface class. A class which contains abstract method is called abstract class
4) Public is default access specifier for interface we don’t have a chance to declare other specifiers. In abstract we have chance to declare with any access specifier

Can you Explain Page lifecycle in .net?
Can you Explain .NET architecture in .net?

What is the difference between primary key and unique key with not null?

Ans: There is no difference between primary key and unique key with not null.

What is boxing and unboxing concepts in .net? 

Ans: Boxing is a process of converting value type into reference type
Unboxing is a process of converting reference type to value type.

What are the differences between value type and reference type?

Ans: Value type contain variable and reference type are not containing value directly in its memory.

Memory is allocated in managed heap in reference type and in value type memory allocated in stack. Reference type ex-class value type-struct, enumeration

Is it possible to host the website from desktop?

Ans: Yes 

Why we go for page rendering in Asp.Net Page life cycle?

Ans: Browser understands an only html control that’s why in page rendering we will convert the aspx controls into html controls.

Write a sample query for self join?

Ans: Select e1.ename, e2.empid from emp e1, emp e2 where e1.empid=e2.mgrid;

Can we change the index of primary key on table?

Ans: No

How to change the name of the table or stored procedure in sql?

Ans: sp_rename oldtablename newtablename
For changing the column name
Sp_rename  ‘tablename.[Oldcolumnname]’,’newcolumnname’,’Column’
Ex:sp_rename ‘tblemp.first’,’namechange’,’Column’

How to find out which index is defined on table?

Ans: sp_helpindex tablename

Can you write the program to find the length of string without using library function?

Ans: for (int i=0; str[i]!=”\n”; i++)
{
Count++;
}

What is the difference between scope_identity() and current_identity()?

Ans: Scope_identity and current _identity both are similar and it will return the last identity value generated in the table.
Scope_Identity will return the identity value in table that is currently in scope

What are difference between GET and POST Methods?

Ans:
GET Method (): 

1) Data is appended to the URL.
2) Data is not secret.
3) It is a single call system
4) Maximum data that can be sent is 256.
5) Data transmission is faster
6) this is the default method for many browsers

POST Method (): 


1) Data is not appended to the URL.
2) Data is Secret
3) it is a two call system.
4) There is no Limit on the amount of data. That is characters any amount of data can be sent.
5) Data transmission is comparatively slow.
6) No default and should be explicitly specified.

What are difference between truncate and delete?

Ans: 1) Delete keep the lock over each row where Truncate keeps the lock on table not on all the row.
2) Counter of the Identity column is reset in Truncate where it is not reset in Delete.
3) Trigger is not fired in Truncate where as trigger is fired in Delete.
4) In TRUNCATE we cannot rollback.
5) In DELETE we can rollback

What is the difference Grid View and between Data Grid (Windows)?

Ans:
1) GridView Control Enables you to add sorting, paging and editing capabilities without writing any code.
2)GridView Control Automatically Supports paging by setting the ‘PagerSetting’ Property.The Page Setting Property supports four Modles 

a. Numeric(by default)
b. Next Previous
c. NumericFirstLast
d. Next PreviousLast

3)It is Used in asp.net
4)GridView Supports RowUpdating and RowUpdated Events.
5)GidView is Capable of Pre-Operations and Post-Operations.
6)GridView Has EditTemplates for this control
7)It has AutoFormat

DataGrid(Windows)

1)DataGid Control raises single Event for operations
2)DataGird Supports the SortCommand Events that occur when a column is Soted.
3)DataGrid Supports UpdataCommand Event that occurs when the UpdateButton is clicked for an item in the grid.
4)DataGrid is used in Windows GUI Application.
5)It doesnot have EditTemplates for this control
6)It doesnot have AutoFormat

If I write System.exit (0); at the end of the try block, will the finally block still execute?

Ans: No in this case the finally block will not execute because when you say system.exit(0),the control immediately goes out of the program, and thus finally never executes.

What are the different levels of State management in ASP.NET?

Ans:
State management is the process by which you maintain state and page information over multiple requests for the same or different pages.

There are 2 types State Management:

1. Client – Side State Management
This stores information on the client's computer by embedding the information into a Web page, a uniform resource locator (url), or a cookie. The techniques available to store the state information at the client end are listed down below:

a. View State – Asp.Net uses View State to track the values in the Controls. You can add custom values to the view state. It is used by the Asp.net page framework to automatically save the values of the page and of each control just prior to rendering to the page. When the page is posted, one of the first tasks performed by page processing is to restore view state.

b. Control State – If you create a custom control that requires view state to work properly, you should use control state to ensure other developers don’t break your control by disabling view state.

c. Hidden fields – Like view state, hidden fields store data in an HTML form without displaying it in the user's browser. The data is available only when the form is processed.

d. Cookies – Cookies store a value in the user's browser that the browser sends with every page request to the same server. Cookies are the best way to store state data that must be available for multiple Web pages on a web site.

e. Query Strings - Query strings store values in the URL that are visible to the user. Use query strings when you want a user to be able to e-mail or instant message state data with a URL.

2. Server – Side State Management
a. Application State - Application State information is available to all pages, regardless of which user requests a page.

b. Session State – Session State information is available to all pages opened by a user during a single visit.

Both application state and session state information is lost when the application restarts. To persist user data between application restarts, you can store it using profile properties.

Abstract Class:

Abstract class is a class which cannot be instantiated. Class should have “Abstract” key word with the name.  In any one of the method of class having abstract method with in it, then it should be define as abstract class. The class which derived the abstract class should have definition of the abstract method. These classes which derived the abstract class and implement the abstract methods call concrete class.

Abstract class may have the definition of function or may not.  Below is the simple example of an abstract class


public abstract class AbstractStudent
    {
        String Roll
        {
            get;
            set;
        }

        String FirstName
        {
            get;
            set;
        }
       
        String LastName
        {
            get;
            set;
        }
       

        Public String GetStudentDetails()
             {

                  // Implementation of Method   
             }

        public String SaveStudentDetails ()
            {
                  // Implementation of Method   
             }

        public abstract String CalculateWage();

    }
So, the class having one abstract method so we need to mention the class as "abstract" .

Difference between Abstract Class and Interface?

Abstract class is a class which cannot be instantiated and which can have methods with definition as well as declaration also. This can be inherited. 

As for Example:

public abstract class AbstractStudent
    {
        String Roll
        {
            get;
            set;
        }

        String FirstName
        {
           get;
           set;
        }
  
        String LastName
        {
           get;
            set;
        }

        Public String GetStudentDetails()
            {
                 // Implementation of Method  
             }

        public String SaveStudentDetails ()
            {
                  // Implementation of Method  
            }

        public abstract String CalculateWage();

    }


Interface can only contain the methods declaration and can be implemented in the class.

As for Example:


Public interface IStudnet
    {
        String Roll
        {
           get;
            set;
        }

        String FirstName
        {
            get;
            set;
        }
   
        String LastName
        {
            get;
            set;
        }
  
        String GetStudentDetails();
        String SaveStudentDetails ();
    }

Below are the few main difference between Abstract Class and Interface

a.    In abstract class method can have definition as well as declaration also. But Interface should have only declarations.
b.    All the Methods are Public as default and don’t have any access Modifier Controls in interface, whereas for abstract class we can have access modifier for methods.
c.    Abstract class can have constructor or destructor, whereas interface not.
d.    Abstract class can’t be part of multiple inheritance and we can implement multiple interface.

What do you mean by String objects are immutable?

String objects are immutable as its state cannot be modified once created. Every time when we perform any operation like add, copy, replace, and case conversion or when we pass a string object as a parameter to a method a new object will be created.

Example:
String str = "ABC";

str.Replace("A","X");

Here Replace() method will not change data that "str" contains, instead a new string object is created to hold data "XBC" and the reference to this object is returned by Replace() method.

So in order to point str to this object we need to write below line.
str = str.Replace("A","X");
Now the new object is assigned to the variable str. earlier object that was assigned to str will take care by garbage collector as this one is no longer in used.

What is dll hell problem in .NET and how it will solve?

Ans: Dll hell, is kind of conflict that occurred previously, due to the lack of version supportability of dll for (within) an application
.NET Framework provides operating system with a global assembly cache. This cache is a repository for all the .net components that are shared globally on a particular machine. When a .net component installed onto the machine, the global assembly cache looks at its version, its public key and its language information and creates a strong name for the component. The component is then registered in the repository and indexed by its strong name, so there is no confusion between the different versions of same component, or DLL

What is a Partial class?

Ans: Instead of defining an entire class, you can split the definition into multiple classes by using partial class keyword. When the application compiled, c# compiler will group all the partial classes together and treat them as a single class. There are a couple of good reasons to use partial classes. Programmers can work on different parts of classes without needing to share same physical file
Ex:
Public partial class employee
{
Public void somefunction()
{
}
}
Public partial class employee
{
Public void function ()
{
}
}

What is difference between constants, read-only and, static?

Constants: The value can’t be changed
Read-only: The value will be initialized only once from the constructor of the class.
Static: Value can be initialized once.

What is the cross page post backing?

Asp.Net 2.0 fixed this with built-in features that allowed us to easily send information from one page to another.

Button control has property PostBackUrl that can be set to URL of any page in our ASP.Net WebSite where we want to transfer all form values to.
Along with that Asp.Net 2.0 Page class has a property PreviousPage that allows us to get reference to the Page object that initiated the postback (in other words to get the actual reference to the Page object of the aspx page on which user clicked the Submit button on a HTML form).

So for example lets create two sample pages in our Web Application:  
  • SourcePage.aspx
  • DestinationPage.aspx
In SoucePage in Html form we will put two TextBox controls (one for First Name and one for Last Name) and one Button component  and set its PostBackUrl property to "~/DestinationPage.aspx".

SourcePage.aspx:
    <form id="form1" runat="server">
        <div>
            First Name:&nbsp;<asp:TextBox ID="FirstName" runat="server"></asp:TextBox><br />
            Last Name:&nbsp;<asp:TextBox ID="LastName" runat="server"></asp:TextBox><br /><br />
            <asp:Button ID="Button1" runat="server" Text="Submit To Destination Page" PostBackUrl="~/CrossPagePostbacks/DestinationPage.aspx" />
        </div>
    </form>

When our user clicks the Submit button, all the values from the HTML Form on SourcePage.aspx will be transfered to the DestinationPage.aspx and we will also be able to get reference to the SourcePage.aspx in our DestinationPage with the PreviousPage property like this:

So in our DestinationPage.aspx.cs code-behind we can easily access two TextBox controls on SourcePage.aspx and show them in two label controls like this:
    protected void Page_Load(object sender, EventArgs e)
    {
        // first check if we had a cross page postback
        if ( (PreviousPage != null) && (PreviousPage.IsCrossPagePostBack) )
        {
            Page previousPage = PreviousPage;
            TextBox firstName = (TextBox)previousPage.FindControl("FirstName");
            TextBox lastName = (TextBox)previousPage.FindControl("LastName");
            // we can now use the values from TextBoxes and display them in two Label controls..
            labelFirstName.Text = firstName.Text;
            labelLastName.Text = lastName.Text;
         }
    }

You probably noticed that we first checked if PreviousPage property of current page (DestinationPage.aspx) is NOT NULL, this is done to avoid running our code in case that user opens our DestinationPage.aspx directly, without running a cross page postback.

Also here we checked the another PreviousPage property called IsCrossPagePostBack to see if we really had a CrossPagePostback.
(If Server.Transfer is used to redirect to this page, IsCrossPagePostBack property will be set to FALSE.

TIP: We can be completely sure that we have a  real CrossPagePostback ONLY IF:
  1. Page.PreviousPage is NOT NULL,
  2. PreviousPage.IsCrossPagePostback is true
This important to check to avoid errors in code.

Now this is very useful and i'm sure you are eager to use this in your next project. But wait, we are not over yet!

Finding the controls on PreviousPage with FindControl method and type-casting them from object to their real type is a little messy.
It feels like there must be a better solution for this!

And here it is: We can use the <%@ PreviousPageType %> directive in the header of our DestinationPage.aspx like this
    <%@ PreviousPageType VirtualPath="~/SourcePage.aspx" %>

to declare our previous page type, and then we can access Public properties of the PreviousPage without typecasting.
Now all we need to do is to create some public properties on our SourcePage.aspx.cs to expose data/Controls we want to the destionation page:
    public partial class SourcePage : System.Web.UI.Page
    {
        public string FormFirstName
        {
            get { return FirstName.Text; }
        }

        public string FormLastName
        {
            get { return LastName.Text; }
        }
    }

And then we can change the Page_Load code in our DestinationPage.aspx to much cleaner code like this:
    protected void Page_Load(object sender, EventArgs e)
    {
        // first check if we had a cross page postback
        if ( (PreviousPage != null) && (PreviousPage.IsCrossPagePostBack) )
        {
            SourcePage prevPage = PreviousPage;

            // we can now use the values from textboxes and display them in two Label controls..
            labelFirstName.Text = prevPage.FormFirstName;
            labelLastName.Text = prevPage.FormLastName;     
        }
    }

SourcePage type used in the code is offcourse name of the partial class defined is SourcePage.aspx.cs that inherits System.Web.UI.Page that is automatically created for us when we created new WebForm in VisualStudio.

This code is much cleaner and easier to follow, there is no ugly typecasting, just simple property values to use to retrieve the data from previous page.


When should you use Abstract Class vs Interface while programming?

 Ans: When we want that sub class must implement all the methods of base class. In such a situation we will implement the interface. In the other hand when we want only some method of base class in our sub class then use base class as abstract class.

What is the difference between application exception and system exception?

Ans: The difference between application exception and system exception is that system exceptions are thrown by CLR and application exceptions are thrown by applications.

What is the difference between authorization and authentication?

Ans: Authorization is a process of allowing or denying resources to particular user or record 

Declaration of authorization is

<authorization>
<allow users=”Suresh, Sanjay”/>
<deny users=”Ramana, Rakesh”>
</authorization>
Sometimes authorization allows the unauthorized persons at that time we will use
<deny users=”?”/>

Authentication means

Authentication is a process where we identify the credentials of user i.e. username, password and create an identity to mention user as an authenticated.  

What is the use of n-tier architecture and 3-tier architecture?


Check this article for 3-tier architecture 3 tier architecture example in asp.net

How to get the version of the assembly?

Ans: lbltxt.text=Assembly. GetExecutingAssembly().GetName().Version.ToString();

What is the location of Global Assembly Cache on the system?

Ans: c:\Windows\assembly

 What is the serialization?

Ans: Serialization is a process of converting object into a stream of bites.

What is synchronization?

Ans: The mechanism needed to block one thread access to the data. If the data is being accessed by another thread.
Synchronization can be accessed by using system.monitor class
A monitor class methods are enter, exit, pulse for this lock statement is also used
Suppose if we need to synchronize some data at that time we need to place that data in this block
Lock
{
}
Whatever the data has been placed into the lock block that data has been blocked

What are the thread priority levels?

Ans: Thread priority levels are five types
         0 - Zero level
         1 - Below Normal
         2 - Normal
         3 - Above Normal
         4 - Highest
By Default priority level is 2

What is the difference between .tostring(), Convert.tostring()?

Ans: The basic difference between them is “Convert” function handles NULLS while
“.ToString()” does not it will throw a NULL reference exception error. So as a good coding
practice using “convert” is always safe.

What is Collation?

Ans: Collation refers to a set of rules that determine how the data is sorted and compared.

What is the difference between Primary key and unique key?

Ans: Primary key does not allow the null values but unique key allows one null value.
Primary key will create clustered index on column but unique key will create non-clustered index by default.

How many web.config files are there in 1 project?

Ans: There might be multiple web.config files for a single project depending on the hierarchy of folders inside the root folder of the project, so for each folder we can use one web.config file

What is the difference between throw and throw ex?
What is the difference between view state and hidden field?

Ans: viewstate is secured hidden field is insecure
Viewstate will store large amount of data but hidden filed will store small amount of data. 

What is the difference between binary serialization and xml serialization?
What is the Difference between read only and constant variables?

Ans: Read only can assign the values at runtime only.
Constant will assign the values at compile time only.
We cannot modify the both variable values.

What is static keyword in .Net?

Ans: Static is same as constant variable but we can change the value of static variable and we can access the variables without creating any instances

What is the use of business logic layer in 3-tier architecture in .net?

Ans: Though a web site could talk to the data access layer directly, it usually goes through another layer called the business layer. The business layer is vital in that it validates the input conditions before calling a method from the data layer. This ensures the data input is correct before proceeding, and can often ensure that the outputs are correct as well. This validation of input is called business rules, meaning the rules that the business layer uses to make “judgments” about the data.

However, business rules don’t only apply to data validation; these rules apply to any calculations or any other action that takes place in the business layer. Normally, it’s best to put as much logic as possible in the business layer, which makes this logic reusable across applications.

One of the best reasons for reusing logic is that applications that start off small usually grow in functionality. For instance, a company begins to develop a web site, and as they realize their business needs, they later decide to add a smart client application and windows service to supplement the web site. The business layer helps move logic to a central layer for “maximum reusability.”


What happens when I enter a URL in my browser and click enter?

You type in the URL and hit go. The browser needs to translate that URL www.somesite.com into an IP address so it knows what computer on the internet to connect to (That URL is just there to make it easier for us humans - kinda like speed-dial for phone numbers I guess). So your browser will see if it already has the appropriate IP address cached away from previous visits to the site. If not, it will make a DNS query to your DNS server (might be your router or your ISP's DNS server) - see http://en.wikipedia.org/wiki/Domain_name… for more on DNS. Once your browser knows what IP to use, it will connect to the appropriate webserver and ask for the page. The webserver then returns the requested page and your browser renders it to the screen.

The firewall will control connections to & from your computer. For the most part it will just be controlling who can connect to your computer and on what ports. For web browsing your firewall generally won't be doing a whole lot.

Your router (see http://en.wikipedia.org/wiki/Router ) essentially guides your request through the network, helping the packets get from computer to computer and potentially doing some NAT (see http://en.wikipedia.org/wiki/Network_add… ) to translate IP addresses along the way (so your internat LAN request can be transitioned onto the wider internet and back).

IP Addresses (see http://en.wikipedia.org/wiki/IP_address ) are unique addresses for computers that basically allow computers to find each other. Think of the IP address as a computer's well address or phone number, you've got to know someone's phone number before you can call them and you've got to know a computer's IP address before you can connect to it. Going back to the start - that's what those URLS and DNS make possible, you don't know John Doe's phone number so you look in the phone book; likewise your computer doesn't know yahoo.com's IP address so it looks in DNS.

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Anonymous said...

Yes these are very ver nice questions thanks for your post

Akash said...

Wats dat qqqqq?

Anonymous said...

good one sir

Anonymous said...

dude you are genius

Anonymous said...

good yaar nice for me as fresher to quick snap before interview

Bvenkat Jeewesh said...

Nice Question. Thanks for Sharing Information.

Bvenkat Jeewesh

[WWE] said...

nice collection of question.... love to read them again... when i got new interview call :)

Suresh Dasari said...

thanks keep visiting

Anonymous said...
This comment has been removed by a blog administrator.
raja said...

we are easily gain from your hardest work...please keep serving people who are all want to develop their knowledge including me.Thanks bro.

Unknown said...

Great Example all !
Thanks

Please Put some Api example on the site

Suresh Dasari said...

@Raja

Thanks

@Darshan

Thanks

Keep visit the site and help me to share with your friends

Anonymous said...

Than k u Master

Anonymous said...

Thanks for sharing the common Freq asked Interview Qs

Deepika Chowdary said...

Thanks for shareing its very useful.

ANANDAN said...

THANK U SIR ITS HELPFUL FOR .NET CANDIATES

Anonymous said...

Thanks for your hard work and sharing with us

Raj said...

thank you for sharing....

Anonymous said...

please post grid view fixed header and footer when scrolling both vertical and horizontal.............
please help me

Anonymous said...

Thanks
nice Questions

sowjanya said...

thanx it is helping me a lot. plz add some more questions suresh... if u can

Varun R Pillai said...

Primary Key are used for referential integrity (pair with FK)
Unique Key are used for data consistency and validation

nithya said...

thanks most useful

nithya said...

i need more
Please update

Anonymous said...

Superb,nice article.....

Roja said...
This comment has been removed by the author.
Roja said...

Good one Suresh.
Thank U for writing good articles for us.
i appreciate your hard work...
Keep posting .......

Anonymous said...

Superb and very helpful ..Thanks brother...

kapil said...

sir, plz give me information of mvc with examples

Anonymous said...

Thankyou so much for this post....

dasthagiri said...

Thank you so much....It is very usefull to us.. keep posting....

Kodexpression said...

Thanks Suresh Sir.......for your valuable information

Anonymous said...

absolutely stunning...

Tahir said...

tohfa kabul kero sir g ....kamal k hai

Bhaumik Patel said...

Amazing article suresh..

google plus 1 said...

What is the difference between primary key and unique key with not null?
Ans: There is no difference between primary key and unique key with not null.

The answer is wrong. there are 3 differences
1. primary key wont allow null value but unique key will do
2. in a table there must but only one Primary Key column but in unique key there may be any number of column
3. Unique Key is Clustered index but primary key is non-clustered.

If any doubt in this let me I can tell you in detail as well!

A Santhosh Reddy said...
This comment has been removed by the author.
A Santhosh Reddy said...

Very Much Interested to read your Articles.
All the posts are very useful

Anonymous said...

great!!

Unknown said...

please you can post an articles about socket in asp.net C#

Unknown said...

Nice one n really helpful

Anonymous said...

Thank u. Suresh ji u r great.

NaukriBox said...

Thanks for sharing
http://www.naukribox.com

DOT NET said...

sir i am read all your valuable post its help me
one question i am asking you related file up loader
i am using file up loader upload image in .aspx page after page post back image path has been clean any solution for this. after page post back image address present there

shekhar said...

well doing good job

Bharat Gunjal said...

its fantastic....u r doing very good job

Tahir said...

tum to chha gaye guru........very nice question...

Unknown said...

Thank you so much suresh sir, need more updates for 1 year experienced

Anonymous said...

khantastic post \m/
-Sagar Sharma

Anonymous said...

Thanks dude forwonderfull article which is simple n easy to understand

praveen said...

Thanks for posting those questions and its really usefull for everyone . these questions will in real time interview...

Dev Anand Purohit said...

Thanks for help
I was looking for this type of document

Thanks a lot

Anonymous said...

hii, it helps me lot for interview preparation.

javeed said...

nice questions..... its help me while i am having interview........

Anonymous said...

Really, it's very nice and helpful interview questions.

Anonymous said...

its really helpful thanx

Pratik said...

Awesome, Nice, Helpful I cdont have any more good adjectives for this post

Unknown said...

Sir i am following your updates daily. i am preparing for the interviews as of now can you send me more interview question with answers for 3 years experience candidates.

Unknown said...

Super

Unknown said...

Sir can u tell me how to host any website

Suresh Dasari said...

@Sumit Gupta...
check this post to host any where http://www.aspdotnet-suresh.com/2012/04/aspnet-host-website-on-local-machine.html

Unknown said...
This comment has been removed by the author.
Unknown said...

Mr.suresh sir this information is very useful for all fresher and for prepare to interview
by rajesh kumar
mail id is malligarajesh88@gmail.com

Unknown said...

i have one doubt can u tell me.

I was created one login form (username and password Only) with set up file in my laptop. i did
installed this setup file in my labtop. It's working well (login button when i click true means login page could be sent or false display check your name or password).

i was installed this (same)setup file in another computer,it's working well. But not working databases that computer. one error display, when i login button click this error display

that error is sql databases not connected
so why this error display... Give me for to this error..
my mail id is malligarajesh88@gmail.com

Unknown said...

Give me solution for to this error

priya said...

its really helpful.can u please tell me how to create a crystal report in .net

Unknown said...

hi thanks

Anonymous said...

Good Article

Unknown said...

very usefull keep going on All the very best.

BHANUSREE VALIVETI said...

my searching is end here..:) thanks good article

kannan said...

great job sir............. keep it up .......

Unknown said...

These questions are basically an interviewer asked,

thanks sir, u done a great job

Anonymous said...

thank u so much ......

Unknown said...

I read this website Daily, I think this is my best site for gain knowledge.

ashok said...

ur telling Interface cannot be inherited and it can be instantiated.. it is wrong.. pls correct

Unknown said...

its grate a lot of knowledge for interview.......
thanks for blog....

Anonymous said...

Thanks for these questions sir,try to upload more and more interview questions here....

Anonymous said...

:)

Anonymous said...
This comment has been removed by a blog administrator.
Raman Ghantiyala said...

Thank you .Net Master..all questions are Up to date and ask-able in While interview. and in good understandable thanks a lot.

Naren said...

Good to revise all these..,

Thanks Boss...

Anonymous said...

Nice article . Thank you very much .

Anonymous said...

great expertise.

Anonymous said...

Thank u so much.
i appreciate you for posting like this articals.
Keep posting .......

Lorena said...

Awesome, thanks! Have a look at the question on ABSTRACT CLASSES. They CAN be inherited.

Thanks again!

Santosh said...

thanks Suresh...its very useful frequently asked question by interviewer.
Santosh Singh

Jignesh Patel said...

IT helped me a lot
Thanks

sasikumar said...

thank you very much thalaiva...

Anonymous said...

Great.!!!!!!! it helped me a lot

Anonymous said...

Suresh! You got appreciated greatly for your dedication.Really its an useful posting for lots of professionals like me. It clears lots of my doubts.



Keep Posting

Suresh

Unknown said...

Thanks for share u r knowledge with me and it is more helpful

Anonymous said...

Really Nice Article

Anonymous said...

Thanks a lott!! really a nice article!!

Unknown said...

Hi Suresh,
Really a very nice job. You seems have more patience & helping nature.
This article will helps to brush up the technology before going to interview.
Thanks a lot....

Anonymous said...

Fantastic, ver useful questions sir. thanks a lot

Iyan K said...

Nice article to recall for an Interview ... Thanks

Anonymous said...

Are These All Question Asking by you only....if yes den its embrassing....

Anonymous said...

Hi Suresh,

Thanks For posting nice question set

add one more question in it.

What is the difference between Server.Transfer and Response.Redirect?

In Server.Transfer page processing transfers from one page to the other page without making a round-trip back to the client’s browser. This provides a faster response with a little less overhead on the server. The clients url history list or current url Server does not update in case of Server.Transfer.

Response.Redirect is used to redirect the user’s browser to another page or site. It performs trip back to the client where the client’s browser is redirected to the new page. The user’s browser history list is updated to reflect the new address.

In Server.Transfer page processing transfers from one page to the other page without making a round-trip back to the client’s browser. This provides a faster response with a little less overhead on the server. The clients url history list or current url Server does not update in case of Server.Transfer.

Response.Redirect is used to redirect the user’s browser to another page or site. It performs trip back to the client where the client’s browser is redirected to the new page. The user’s browser history list is updated to reflect the new address.

Unknown said...

Fantastic Article....

Abhay Kumar said...

Thanx a ton it was really helpful.. :)

Unknown said...

Good job Suresh

manikya reddy said...

it is very useful to clear f2f interview

Anonymous said...

Suresh nice job...

Anonymous said...

send some more questions for 3+ years experience in .NET

Unknown said...

hello suresh, i need exactly oops concepts(generics,delegates,overloading and ovrriding) where we can used in project and which scenario we used explain????

Unknown said...

good one My dear friend

Anonymous said...

good

Anonymous said...

good

Unknown said...

What is the Query to select records in sql server 2008 like this blow

After select Table
----------
id pname qunt unt price stockdt
------------------------------------------------------
1 patato 1 kg 10.00 10/4/13
2 tamato 1 kg 12.00 10/4/13
3 brinjal 1 kg 22.00 8/4/13
4 Milk 1 Ltr 24.00 9/4/2013


from stock in table as below

table
----------
id pname qunt unt price stockdt
-------------------------------
1 patato 1 kg 8.00 8/4/13
2 tamato 1 kg 10.00 8/4/13
3 brinjal 1 kg 22.00 8.4.13
4 milk 1 Ltr 23.00 8/4/2013
5 patato 1 kg 9.00 9/4/13
6 milk 1 Ltr 24.00 9/4/2013
7 patato 1 kg 10.00 10/4/13
8 tamato 1 kg 12.00 10/4/13











OM said...

thnx a lot sir.......
i never visited a blog like.
it is too helpful and encouraging..
i heartly appreciating u....

Unknown said...

nice thx

Anonymous said...

I want you to upload more videos of asp.net

Unknown said...

Sir,Pls give me some idea about asp.net mvc

Anonymous said...

Thanku...

Unknown said...

these are very very nice questions thanks for your post.

mohd faizan

Unknown said...

Interface vs Abstract: Abstract cannot be instantiated but we can inherit. Interface it cannot be inherit it can be instantiate --> This answer is wrong, I dont think interface can be instantiate and cannot be inherit? pls explain

Unknown said...

these are very nice question for f2f interview.

Unknown said...

Thanks

Unknown said...

Nice help for Freshers if you can add more i would like to give questions which i faced.If you can just post them with answers

Unknown said...


1.What is GAC ??
2.What is Assembly?
3.How to place DLL in GAC??
4.What is pobm with DLL??
5.What is appSettings ??in webconfig>
6.What is tag in webconfig?
7.Property?.when Master page loads in Which Event?User Control and custom control ??


8.Why interface??
9.what is ajax?how it works with example
10.validate textbox with email using jquery
11.what is Delegate???why ??example.realtime
12.Diffrence between datareader and dataset??
13.which function for execution of query?in .net
14.how many tables can be in Dataset?
15.Main class in dot net ?which contains all clasees.
16 In Ajax will page redirect ??will it go to server for procees?

17.What is ViewState???Why >>>??real time Scenario?>
18.what is exception?object is not with the refrence?
19.If UserControl is used in web page then if 1 button in usercontrol if we click then that value in textbox of user control should go to web page text box.and Vice a versa.??
20.what are Validators??if they are client side then if i disable the javascript in my browser and in page there are 100 text box with validations then if i forgot to fill one textbox what will happen page will redirect or not??
21.if not then which function we can use on server side to check all boxes are valid ??
22.How to put Checkbox in Gridview??by button and code?
23.stored Procedure ??if there are two statements in Procedure then how can we take both result set in datareader?
Please try to understand them.Thank you.

Bharti said...
This comment has been removed by a blog administrator.
Unknown said...

Nice Question for Preparing Interview.?

dhanalakshmi said...

hi suresh send me 2years experience interview questions. .

venkat said...

Thank's for sharing valuable information,it is helpful to me...........

Anonymous said...

Nice Good Job

Unknown said...

thak u .. but i con't understand

Unknown said...

Great Work.. Thanks for the page..

Unknown said...

I think first answer is wrong in the following question.

What are the differences between Abstract and interface?

Ans:
1) Abstract cannot be instantiated but we can inherit. Interface it cannot be inherit it can be instantiate
2) Interface contain only declarations no definitions. Abstract contain declarations and definitions.
3) The class which contains only abstract methods is interface class. A class which contains abstract method is called abstract class
4) Public is default access specifier for interface we don’t have a chance to declare other specifiers. In abstract we have chance to declare with any access specifier

Unknown said...

hi suresh
you ara given best info
give more on practicle exp questions

pls send me code for wpf dml operations using datagrid control

Arvind Kumar said...

Nice Post

Unknown said...

Very Very Useful in interviews.Thank you Very Much.

Vishu_Sukhdev said...

Good one. I faced same questions on my interview but now i know the answer.
Thank You!

Unknown said...

nice question,,really fantastic...

Unknown said...

thanq very much sir really fentastic q&a

Unknown said...

Good one

Arvind Pandey said...

ARE GREAT MAN..................I LIKE IT..

Bhagwat Prasad Sharma said...

really nice .net interview question collection by you...

Unknown said...

Superb and very helpful for freshers Thank u Sir

Unknown said...

Very nice questions..please send me 2 years experience interview questions.

dhruv said...

Thanks.

Anonymous said...

very good collection

Unknown said...

Thanks a lot.......

Anonymous said...

very useful document.. great suresh

Anonymous said...

hi suresh send me MVC project code

Harisha said...

Awesome sir really it will help to many students

Ambily Ravi said...

thank you....helpful....

arjunan said...

Hi Suresh,

you made a mistake here.
In abstract class method can have definition as well as declaration also. But Interface should have only definition.

Interface should hold only the declarations..not definitions

prateek said...

These are the best questions available on the internet,thanks a ton
Mostly all question were from this list in one of the company I gave interview and written test. :)

JO~ said...

This is a good post
but i want to knoew ans of my que:
how to handle exception "connection doesnot access" when it is logged in log file.

how can we troubleshoot this?

RADHIKA said...

Thank you for the information. Can u include some questions regarding delegates, threading and ADO.NET as well?

Unknown said...

Thank You very much suresh we Are learning new things from you

rajesh said...

Primary Key:

i) Can be only one in a table

ii) It never allows null values

iii) Primary Key is unique key identifier and can not be null and must be unique.

Unique Key:

i) Can be more than one unique key in one table.

ii) Unique key can have null values

iii) It can’t be candidate key

iv) Unique key can be null and may not be unique.
why put wrong ans. if you don't know so don't put wrong ans.

rajesh said...

yes you can change primary key index.

mala.....totally Positive said...

toooo good...gr8 help for the people like me looking for a change....keep the good work
:)

Anonymous said...

thanks sir ...ji
but please also post jquiery Javascript and ajax interview questions answered please please

Abhejeet Singh said...

dude we want please write some thing practical on windows azure.

Unknown said...

good job

Anonymous said...

all your notes are very good,this one also.........

mathan.jithu said...
This comment has been removed by a blog administrator.
Anonymous said...

helpful very good.........

Anonymous said...

very helpful........
thank you for sharing

Anonymous said...

Excellent...keep posting.

Anonymous said...

Thanku For ur valuable information.. can u plz some more C# questions and sql question and answers..!!!

Anonymous said...

This is really nice document. Thank you so much for posting this document

Shravan said...

Thanking You Suresh for shraing such imporatant Questions

Anonymous said...

Contents are wrong. I found some wrong statements on this article.
Please have correct information so that users gets the right information .(eg. review what is written for interface)

Anonymous said...

This is Venu



very nice work,keep continue

Anonymous said...

Thank You ..its very much helpful...

.Net Training in Chennai said...

Vey Informative.

Anonymous said...

execellent que and ans....


very nice information..

Anonymous said...

Thanku its very helpful for me..

Dattatri Kashiwale said...

Thanks a lot sir..... very very thanku bro.....

Unknown said...

Thanks Very nice and very help for beginners

Dhiraj said...

very very helpful,thanks a lot....

Allan said...

very helpful.

Anonymous said...

Thankyou bro

Unknown said...

When should you use Abstract Class vs Interface while programming?

Ans: When we want that sub class must implement all the methods of base class. In such a situation we will implement the interface. In the other hand when we want only some method of base class in our sub class then use base class as abstract class.

Sir ,is this ans is right.......
If yes then what is this

Abstract Class:

-While inheriting abstract class all abstract methods must be override
-


Mrkraju From Velagadurru said...

Thank you Suresh for helping many people like me..

Ganesh said...

Help me lot

LAXMINARAYANA said...

Thank you

Ketan said...

Thank you sir , it's very helpful for all .net beginner

Unknown said...

very very nice... i have gone through all quesion and hav build a confidence to face tha interviewer now... LIKE (y)

Anonymous said...

Nive Post.. Thank you sir

Anonymous said...

Very nice and cover most of basic topics

Anonymous said...

sir, can you please help me with datalist and repeater paging with first,last,previous,next buttons using stored procedure. my email is miakayuki2011@gmail.com

manoj kumar said...

thanks for this sharing

Unknown said...

you are genius suresh great.....

Anonymous said...

really you are doing good job. I had never entered comments for any page. but i cant stop doing it here. Think from this how best you are. Thank you for giving such a wonderful post day by day. i am very big fan of you. We need your support in upcoming days too.

Anonymous said...

really you are doing good job. I had never entered comments for any page. but i cant stop doing it here. Think from this how best you are. Thank you for giving such a wonderful post day by day. i am very big fan of you. We need your support in upcoming days too.

Anonymous said...

Thanx for posting this interview question that we must know as fresher or developer

Anonymous said...

Perhaps you are all superb software developers but your English skills need improvement.

Unknown said...

Thank You Sir....... These questions are very helpful for .Net Beginners.

Anonymous said...

Today only i have seen this website. Its very useful for all .net beginners. Me too .net beginner, i need more explained examples from starting level.

I have one doubt. I am facing this problem when i am installing
Error 1311. Source file not found:
D:\vs\_17962_RTL_x86_enu_VCTools_Spyxx_Utility.cab.
Verify that the file exists and that you can access it.

Kindly tell me the solution for this.

Anonymous said...

superb <3

Anonymous said...

Thanks Dude

Indrasen said...

Thanks a lot..this one is a really great pool of questions.

Anonymous said...

nice post

Anonymous said...

awesomeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

Anonymous said...

thank u

karuna said...

thhh

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