Basic guide lines for .Net(C#, ASP.NET) programming

Technical guide lines for  .Net(C#, ASP.NET) programming

1) Sort all the namespaces alphabetically as shown below

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

2) Use #region for Segregation

#region Page Event Handlers

#region UI Event Handlers

#region Helper Methods

3) Always initialize String type with String.empty

Wrong:

String CardNo = "";

Correct:

String CardNo = String.empty;

4)Avoid parameters
When you call any method in the C# language that was not in-lined, the run time will actually physically copy the variables you pass as arguments to the formal parameter slot memory in the called method. It causes stack memory operations and incurs a performance hit. It is faster to minimize arguments, and even use constants in the called methods instead of passing them arguments.

5) Avoid local variables

When you call a method in your C# program, the run time allocates a separate memory region to store all the local variable slots. This memory is allocated on the stack even if you do not access the variables in the function call. Therefore, you can call methods faster if they have fewer variables in them.

  6) Use arrays
In the .NET Framework, you have many options for collections, such as the List type, and various other types such as ArrayList. While these types are convenient and should be used when necessary, it is always more efficient to use a simple array if this is possible. The reason for this is that the more complex collections such as List are actually composed of internal arrays. They add logic to avoid the burden of managing the array size on each use. However, if you do not need this logic, or can adjust your code so that the logic is not needed, using an array will be faster.

 
7)Use StringBuilder
If you are doing significant appending of strings using the C# language, the StringBuilder type can improve performance. This is because the string type is immutable and cannot be changed without reallocating the entire object. Sometimes, using strings instead of StringBuilder for concatenations is faster; this is typically the case when using very small strings or doing infrequent appends.

8) Use static fields

Here, we note that static fields are faster than instance fields, for the same reason that static methods are faster than instance methods. When you load a static field into memory, you do not need the runtime to resolve the instance expression. Loading an instance field must have the object instance first resolved. In fact, even in an object instance, loading a static field is faster because no instance expression instruction is ever used.

9) Comparing Non-Case-Sensitive Strings

In an application sometimes it is necessary to compare two string variables, ignoring the cases. The tempting and traditionally approach is to convert both strings to all lower case or all upper case and then compare them, like such:

str1.ToLower() == str2.ToLower()

However repetitively calling the function ToLower() is a bottleneck in performace. By instead using the built-in string.Compare() function you can increase the speed of your applications.

To check if two strings are equal ignoring case would look like this:

string.Compare(str1, str2, true) == 0 //Ignoring cases

The C# string.Compare function returns an integer that is equal to 0 when the two strings are equal.

10) Use && and || operators

When building if statements, simply make sure to use the double-and notation (&&) and/or the double-or notation (||), (in Visual Basic they are AndAlso and OrElse).

If statements that use & and | must check every part of the statement and then apply the "and" or "or". On the other hand, && and || go thourgh the statements one at a time and stop as soon as the condition has either been met or not met.

Executing less code is always a performace benefit but it also can avoid run-time errors, consider the following C# code:

if (object1 != null && object1.runMethod())

If object1 is null, with the && operator, object1.runMethod()will not execute.

 If the && operator is replaced with &, object1.runMethod() will run even if object1 is already known to be null, causing an exception.

11)Lazy Instantiation/Initialization

The Singleton design pattern is often used to provide a single global instance of a class. Sometimes it's the case that a particular singleton won't be needed during an application run. It's generally good practice to delay the creation of any object until it's needed, unless there's a specific need to the contrary - for instance, to pre-cache slow-initializing objects such as database connections. The "double-checked locking" pattern is useful in these situations, as a way to avoid synchronization and still ensure that a needed action is only performed once. Lazy initialization is a technique that can enhance the performance of an entire application through object reduction.

12)Working with Objects and Value Types

Objects are expensive to use, partly because of the overhead involved in allocating memory from the heap (which is actually well-optimized in .NET) and partly because every created object must eventually be destroyed. The destruction of an object may take longer than its creation and initialization,especially if the class contains a custom finalization routine. Also, the garbage collector runs in an indeterministic way; there's no guarantee that an object's memory will be immediately reclaimed when it goes out of scope, and until it's collected, this wasted memory can adversely affect performance.

It's necessary to understand garbage collection to appreciate the full impact of using objects. The single most important fact to know about the garbage collector is that it divides objects into three "generations": 0, 1, and 2. Every object starts out in generation 0; if it survives (if at least one reference is maintained) long enough, it goes to 1; much later, it transitions to 2. The cost of collecting an object increases with each generation. For this reason, it's important to avoid creating unnecessary objects, and to destroy each reference as quickly as possible. The objects that are left will often be long-lived and won't be destroyed until application shutdown.

13) Using the 'Sealed' Keyword

Wherever extensibility is not required, you should use the sealed keyword. This makes your design easier to understand, as someone can tell at a glance if a certain class or method isn't meant to be extended or overridden. It also increases the chances that the compiler will inline code.

15) Use Page.IsPostback to avoid unnecessary processing on a round trip.

 



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WCF Interview Questions Part2

 

What is Transport and Message Reliability?


Transport reliability (such as the one offered by TCP) offers point-to-point guaranteed delivery at the network packet level, as well as guarantees the order of the packets. Transport reliability is not resilient to dropping network connections and a variety of other communication problems.




Message reliability deals with reliability at the message level independent of how many packets are required to deliver the message. Message reliability provides for end-to-end guaranteed delivery and order of messages, regardless of how many intermediaries are involved, and how many network hops are required to deliver the message from the client to the service.


What are contracts in WCF?

In WCF, all services expose contracts. The contract is a platform-neutral and standard way of describing what the service does.

WCF defines four types of contracts.
Service contracts
Describe which operations the client can perform on the service.


There are two types of Service Contracts.


ServiceContract - This attribute is used to define the Interface.


OperationContract - This attribute is used to define the method inside Interface.


[ServiceContract]
interface IMyContract
{


[OperationContract]
string MyMethod( );
}


class MyService : IMyContract
{


public string MyMethod( )
{
return "Hello World";
}




Data contracts

Define which data types are passed to and from the service. WCF defines implicit contracts for built-in types such as int and string, but we can easily define explicit opt-in data contracts for custom types.


There are two types of Data Contracts.


DataContract - attribute used to define the class


DataMember - attribute used to define the properties.


[DataContract]
class Contact
{


[DataMember]
public string FirstName;

[DataMember]

public string LastName;
}


If DataMember attributes are not specified for a properties in the class, that property can't be passed to-from web service.


Fault contracts


Define which errors are raised by the service, and how the service handles and propagates errors to its clients.

Message contracts

Allow the service to interact directly with messages. Message contracts can be typed or untyped, and are useful in interoperability cases and when there is an existing message format we have to comply with.

What is endpoint in WCF?

Every service must have Address that defines where the service resides, Contract that defines what the service does and a Binding that defines how to communicate with the service. In WCF the relationship between Address, Contract and Binding is called Endpoint.
The Endpoint is the fusion of Address, Contract and Binding.

Where we can host WCF services?


Every WCF services must be hosted somewhere. There are three ways of hosting WCF services.
They are

1. IIS

2. Self Hosting
3. WAS (Windows Activation Service)

For more details see http://msdn.microsoft.com/en-us/library/bb332338.aspx

What is service and client in perspective of data communication?

A service is a unit of functionality exposed to the world.

The client of a service is merely the party consuming the service.

There are four core security features that WCF addresses:-

Confidentiality: This feature ensures that the information does not go in wrong hands when it travels from the sender to the receiver.

Integrity: This feature ensures that the receiver of the message gets the same information that the sender sends without any data tampering.

Authentication: This feature verifies who the sender is and who the receiver is.

Authorization: This feature verifies whether the user is authorized to perform the action they are requesting from the application.










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WCF interview Questions Part1

Web Services

1.It Can be accessed only over HTTP

2.It works in stateless environment

WCF

WCF is flexible because its services can be hosted in different types of applications. The following lists several common scenarios for hosting WCF services:

IIS

WAS

Self-hosting

Managed Windows Service


What are the various ways of hosting a WCF service?

Self hosting the service in his own application domain. This we have already covered in the first section. The service comes in to existence when you create the object of ServiceHost class and the service closes when you call the Close of the ServiceHost class.

Host in application domain or process provided by IIS Server.

Host in Application domain and process provided by WAS (Windows Activation Service) Server.


What is three major points in WCF?

Address --- Specifies the location of the service which will be like http://Myserver/MyService.Clients will use this location to communicate with our service.


Binding --- Specifies how the two parties will communicate in term of transport and encoding and protocols
Contract --- Specifies the interface between client and the server. It's a simple interface with some attribute.

What is the difference WCF and Web services?

Web services can only be invoked by HTTP (traditional web service with .asmx). While WCF Service or a WCF component can be invoked by any protocol (like http, tcp etc.) and any transport type.
Second web services are not flexible. However, WCF Services are flexible. If you make a new version of the service then you need to just expose a new end. Therefore, services are agile and which is a very practical approach looking at the current business trends.

We develop WCF as contracts, interface, operations, and data contracts. As the developer we are more focused on the business logic services and need not worry about channel stack. WCF is a unified programming API for any kind of services so we create the service and use configuration information to set up the communication mechanism like HTTP/TCP/MSMQ etc

For more details, read http://msdn.microsoft.com/en-us/library/aa738737.aspx

What are various ways of hosting WCF Services?


There are three major ways of hosting a WCF services

• Self-hosting the service in his own application domain. This we have already covered in the first section. The service comes in to existence when you create the object of Service Host class and the service closes when you call the Close of the Service Host class.

• Host in application domain or process provided by IIS Server.

• Host in Application domain and process provided by WAS (Windows Activation Service) Server.

More details http://www.dotnetfunda.com/articles/article221.aspx#whatarethevariouswaysofhostingaWCFservice

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Technical guidelines for .net programming

1) Avoid parameters
When you call any method in the C# language that was not in-lined, the runtime will actually physically copy the variables you pass as arguments to the formal parameter slot memory in the called method. It causes stack memory operations and incurs a performance hit. It is faster to minimize arguments, and even use constants in the called methods instead of passing them arguments.

2) Avoid local variables

When you call a method in your C# program, the runtime allocates a separate memory region to store all the local variable slots. This memory is allocated on the stack even if you do not access the variables in the function call. Therefore, you can call methods faster if they have fewer variables in them.

3) Use arrays
In the .NET Framework, you have many options for collections, such as the List type, and various other types such as ArrayList. While these types are convenient and should be used when necessary, it is always more efficient to use a simple array if this is possible. The reason for this is that the more complex collections such as List are actually composed of internal arrays. They add logic to avoid the burden of managing the array size on each use. However, if you do not need this logic, or can adjust your code so that the logic is not needed, using an array will be faster.

4) Use StringBuilder
If you are doing significant appending of strings using the C# language, the StringBuilder type can improve performance. This is because the string type is immutable and cannot be changed without reallocating the entire object. Sometimes, using strings instead of StringBuilder for concatenations is faster; this is typically the case when using very small strings or doing infrequent appends.

5) Use static fields
Here, we note that static fields are faster than instance fields, for the same reason that static methods are faster than instance methods. When you load a static field into memory, you do not need the runtime to resolve the instance expression. Loading an instance field must have the object instance first resolved. In fact, even in an object instance, loading a static field is faster because no instance expression instruction is ever used.

6) Comparing Non-Case-Sensitive Strings

In an application sometimes it is necessary to compare two string variables, ignoring the cases. The tempting and traditionally approach is to convert both strings to all lower case or all upper case and then compare them, like such:
str1.ToLower() == str2.ToLower()

However repetitively calling the function ToLower() is a bottleneck in performace. By instead using the built-in string.Compare() function you can increase the speed of your applications.

To check if two strings are equal ignoring case would look like this:

string.Compare(str1, str2, true) == 0 //Ignoring cases
The C# string.Compare function returns an integer that is equal to 0 when the two strings are equal.

7) Use && and || operators

When building if statements, simply make sure to use the double-and notation (&&) and/or the double-or notation (||), (in Visual Basic they are AndAlso and OrElse).

If statements that use & and | must check every part of the statement and then apply the "and" or "or". On the other hand, && and || go thourgh the statements one at a time and stop as soon as the condition has either been met or not met.

Executing less code is always a performace benefit but it also can avoid run-time errors, consider the following C# code:

if (object1 != null && object1.runMethod())
If object1 is null, with the && operator, object1.runMethod()will not execute.
If the && operator is replaced with &, object1.runMethod() will run even if object1 is already known to be null, causing an exception.

8)Lazy Instantiation/Initialization

The Singleton design pattern is often used to provide a single global instance of a class. Sometimes it's the case that a particular singleton won't be needed during an application run. It's generally good practice to delay the creation of any object until it's needed, unless there's a specific need to the contrary - for instance, to pre-cache slow-initializing objects such as database connections. The "double-checked locking" pattern is useful in these situations, as a way to avoid synchronization and still ensure that a needed action is only performed once. Lazy initialization is a technique that can enhance the performance of an entire application through object reduction.


9)Working with Objects and Value Types

Objects are expensive to use, partly because of the overhead involved in allocating memory from the heap (which is actually well-optimized in .NET) and partly because every created object must eventually be destroyed. The destruction of an object may take longer than its creation and initialization,especially if the class contains a custom finalization routine. Also, the garbage collector runs in an indeterministic way; there's no guarantee that an object's memory will be immediately reclaimed when it goes out of scope, and until it's collected, this wasted memory can adversely affect performance.

It's necessary to understand garbage collection to appreciate the full impact of using objects. The single most important fact to know about the garbage collector is that it divides objects into three "generations": 0, 1, and 2. Every object starts out in generation 0; if it survives (if at least one reference is maintained) long enough, it goes to 1; much later, it transitions to 2. The cost of collecting an object increases with each generation. For this reason, it's important to avoid creating unnecessary objects, and to destroy each reference as quickly as possible. The objects that are left will often be long-lived and won't be destroyed until application shutdown.

10) Using the 'Sealed' Keyword
Wherever extensibility is not required, you should use the sealed keyword. This makes your design easier to understand, as someone can tell at a glance if a certain class or method isn't meant to be extended or overridden. It also increases the chances that the compiler will inline code.

11) Use Page.IsPostback to avoid unnecessary processing on a round trip.









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Sonata .NET interview Questions

Last week one of my friend attended SONATA Software .NET interview....

Here are the Questions:

1.what is a constructor ?
2.types constructor ?
3.how can we call parameterized constructor from Default constructor & Vice versa.. ?
4.Difference between Interface & Abstract class ?
5.What is WCF ?
6.Difference between WebService & WCF ?
7.Difference between viewstate & Session state ?
8.Difference between delete & truncate ?
9.Difference between virtual & abstract key words?
10.types of variables Private Protected Public
11.How can u swap 2 variables values without using temp variables
12.Types of binding(ploymorphism).
13.Difference between build & rebuild ?
14. Scenario in SQL SERVER :
Emp table with GRADE(A,B,C),SAL,EMPID
Write a single update statement
to add
for A grade 1000 bonus,B 3000, c 5000
u need to write a single statement to upadte the records based on the Grade
15.Difference between Array.Clone & Array.Copy
16.Can we Rollback Truncate ?
Ans :Yes: like this
Write truncate within transaction
Begin Tran
truncate table tablename
ROLLBACK

SONATA INTERVIEW QUESTIONS FOR EXPERIENCED


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Set the Cacheability of an ASP.NET Page declaratively

Set the Cacheability of an ASP.NET Page declaratively

The cacheability of a page or user control refers to whether or not a page can be cached on a device during its response life cycle. These devices include the client (browser) making the request, the Web server responding to the request, and any cache-capable devices, such as proxy servers, that are in the request or response stream.
If you know at design time what cacheability setting you need for a page, you can set cacheability declaratively. The page will then use the same cacheability settings for all requests.

To set a page's cacheability declaratively
1. Include an @ OutputCache directive in the page and define Duration and VaryByParam attributes.
2. Include a Location attribute in the @ OutputCache directive and define its value as one of the following values in the OutputCacheLocation enumeration: Any, Client, Downstream, Server, ServerAndClient, or None.
The following code shows how to set the page's cacheability to 60 seconds:
<%@ OutputCache Duration="60" VaryByParam="None"%>
Note
The default setting is Any. If you do not define a Location attribute, the page output can be cached on all cache-capable network devices that are involved in the response. These include the requesting client, the origin server, and any proxy servers through which the response passes.

To set a page's cacheability declaratively using a cache profile
1. Define a cache profile in your application's Web.config file and in the profile, include duration and varyByParam settings.
The following configuration element defines a cache profile named Cache30Seconds, which will cache the page on the server for 30 seconds.


2. Include an @ OutputCachedirective in each ASP.NET page that uses the profile, and set the CacheProfile attribute to the name of the cache profile defined in your Web.config file.
The following code specifies that the page should use the cache profile named Cache30Seconds:

<%@ OutputCache CacheProfile="Cache30Seconds" %>


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.NET Framework Interview Questions

.NET Framework Interview Questions
What is the Microsoft.NET?
.NET is a set of technologies designed to transform the internet into a full scale distributed platform. It provides new ways of connecting systems, information and devices through a collection of web services. It also provides a language independent, consistent programming model across all tiers of an application.
The goal of the .NET platform is to simplify web development by providing all of the tools and technologies that one needs to build distributed web applications.
What is the .NET Framework?
The .NET Framework is set of technologies that form an integral part of the .NET Platform. It is Microsoft's managed code programming model for building applications that have visually stunning user experiences, seamless and secure communication, and the ability to model a range of business processes.
The .NET Framework has two main components: the common language runtime (CLR) and .NET Framework class library. The CLR is the foundation of the .NET framework and provides a common set of services for projects that act as building blocks to build up applications across all tiers. It simplifies development and provides a robust and simplified environment which provides common services to build application. The .NET framework class library is a collection of reusable types and exposes features of the runtime. It contains of a set of classes that is used to access common functionality.
What is CLR?
The .NET Framework provides a runtime environment called the Common Language Runtime or CLR. The CLR can be compared to the Java Virtual Machine or JVM in Java. CLR handles the execution of code and provides useful services for the implementation of the program. In addition to executing code, CLR provides services such as memory management, thread management, security management, code verification, compilation, and other system services. It enforces rules that in turn provide a robust and secure execution environment for .NET applications.
What is CTS?
Common Type System (CTS) describes the data types that can be used by managed code. CTS define how these types are declared, used and managed in the runtime. It facilitates cross-language integration, type safety, and high performance code execution. The rules defined in CTS can be used to define your own classes and values.
What is CLS?
Common Language Specification (CLS) defines the rules and standards to which languages must adhere to in order to be compatible with other .NET languages. This enables C# developers to inherit from classes defined in VB.NET or other .NET compatible languages.
What is managed code?
The .NET Framework provides a run-time environment called the Common Language Runtime, which manages the execution of code and provides services that make the development process easier. Compilers and tools expose the runtime's functionality and enable you to write code that benefits from this managed execution environment. The code that runs within the common language runtime is called managed code.

What is MSIL?
When the code is compiled, the compiler translates your code into Microsoft intermediate language (MSIL). The common language runtime includes a JIT compiler for converting this MSIL then to native code.
MSIL contains metadata that is the key to cross language interoperability. Since this metadata is standardized across all .NET languages, a program written in one language can understand the metadata and execute code, written in a different language. MSIL includes instructions for loading, storing, initializing, and calling methods on objects, as well as instructions for arithmetic and logical operations, control flow, direct memory access, exception handling, and other operations.
What is JIT?
JIT is a compiler that converts MSIL to native code. The native code consists of hardware specific instructions that can be executed by the CPU.
Rather than converting the entire MSIL (in a portable executable[PE]file) to native code, the JIT converts the MSIL as it is needed during execution. This converted native code is stored so that it is accessible for subsequent calls.
What is portable executable (PE)?
PE is the file format defining the structure that all executable files (EXE) and Dynamic Link Libraries (DLL) must use to allow them to be loaded and executed by Windows. PE is derived from the Microsoft Common Object File Format (COFF). The EXE and DLL files created using the .NET Framework obey the PE/COFF formats and also add additional header and data sections to the files that are only used by the CLR.
What is an application domain?
Application domain is the boundary within which an application runs. A process can contain multiple application domains. Application domains provide an isolated environment to applications that is similar to the isolation provided by processes. An application running inside one application domain cannot directly access the code running inside another application domain. To access the code running in another application domain, an application needs to use a proxy.
How does an AppDomain get created?
AppDomains are usually created by hosts. Examples of hosts are the Windows Shell, ASP.NET and IE. When you run a .NET application from the command-line, the host is the Shell. The Shell creates a new AppDomain for every application. AppDomains can also be explicitly created by .NET applications.
What is an assembly?
An assembly is a collection of one or more .exe or dll’s. An assembly is the fundamental unit for application development and deployment in the .NET Framework. An assembly contains a collection of types and resources that are built to work together and form a logical unit of functionality. An assembly provides the CLR with the information it needs to be aware of type implementations.

What are the contents of assembly?
A static assembly can consist of four elements:
 Assembly manifest - Contains the assembly metadata. An assembly manifest contains the information about the identity and version of the assembly. It also contains the information required to resolve references to types and resources.
 Type metadata - Binary information that describes a program.
 Microsoft intermediate language (MSIL) code.
 A set of resources.

What are the different types of assembly?
Assemblies can also be private or shared. A private assembly is installed in the installation directory of an application and is accessible to that application only. On the other hand, a shared assembly is shared by multiple applications. A shared assembly has a strong name and is installed in the GAC.
We also have satellite assemblies that are often used to deploy language-specific resources for an application.

What is a dynamic assembly?
A dynamic assembly is created dynamically at run time when an application requires the types within these assemblies.

What is a strong name?
You need to assign a strong name to an assembly to place it in the GAC and make it globally accessible. A strong name consists of a name that consists of an assembly's identity (text name, version number, and culture information), a public key and a digital signature generated over the assembly. The .NET Framework provides a tool called the Strong Name Tool (Sn.exe), which allows verification and key pair and signature generation.

What is GAC?
What are the steps to create an assembly and add it to the GAC?
The global assembly cache (GAC) is a machine-wide code cache that stores assemblies specifically designated to be shared by several applications on the computer. You should share assemblies by installing them into the global assembly cache only when you need to.
Steps
- Create a strong name using sn.exe tool eg: Sn -k mykey.snk
- In AssemblyInfo.cs, add the strong name eg: [assembly: AssemblyKeyFile ("mykey.snk")]
- recompile project, and then install it to GAC in two ways:
 drag & drop it to assembly folder (C:\WINDOWS\assembly OR C:\WINNT\assembly) (shfusion.dll tool)
 gacutil -i abc.dll

What is the caspol.exe tool used for?
The caspol tool grants and modifies permissions to code groups at the user policy, machine policy, and enterprise policy levels.

What is a garbage collector?
A garbage collector performs periodic checks on the managed heap to identify objects that are no longer required by the program and removes them from memory.

What are generations and how are they used by the garbage collector?
Generations are the division of objects on the managed heap used by the garbage collector. This mechanism allows the garbage collector to perform highly optimized garbage collection. The unreachable objects are placed in generation 0, the reachable objects are placed in generation 1, and the objects that survive the collection process are promoted to higher generations.

What is Ilasm.exe used for?
Ilasm.exe is a tool that generates PE files from MSIL code. You can run the resulting executable to determine whether the MSIL code performs as expected.
What is Ildasm.exe used for?
Ildasm.exe is a tool that takes a PE file containing the MSIL code as a parameter and creates a text file that contains managed code.
What is the ResGen.exe tool used for?
ResGen.exe is a tool that is used to convert resource files in the form of .txt or .resx files to common language runtime binary .resources files that can be compiled into satellite assemblies.
Explain the Event Life cycle of ASP.NET 2.0?
The events occur in the following sequence. Its best to turn on tracing(<% @Page Trace=”true”%>) and track the flow of events :
PreInit – This event represents the entry point of the page life cycle. If you need to change the Master page or theme programmatically, then this would be the event to do so. Dynamic controls are created in this event.
Init – Each control in the control collection is initialized.
Init Complete* - Page is initialized and the process is completed.
PreLoad* - This event is called before the loading of the page is completed.
Load – This event is raised for the Page and then all child controls. The controls properties and view state can be accessed at this stage. This event indicates that the controls have been fully loaded.
LoadComplete* - This event signals indicates that the page has been loaded in the memory. It also marks the beginning of the rendering stage.
PreRender – If you need to make any final updates to the contents of the controls or the page, then use this event. It first fires for the page and then for all the controls.
PreRenderComplete* - Is called to explicitly state that the PreRender phase is completed.
SaveStateComplete* - In this event, the current state of the control is completely saved to the View State.
Unload – This event is typically used for closing files and database connections. At times, it is also used for logging some wrap-up tasks.


The events marked with * have been introduced in ASP.NET 2.0.
You have created an ASP.NET Application. How will you run it?
With ASP.NET 2.0, Visual Studio comes with an inbuilt ASP.NET Development Server to test your pages. It functions as a local Web server. The only limitation is that remote machines cannot access pages running on this local server. The second option is to deploy a Web application to a computer running IIS version 5 or 6 or 7.
Explain the AutoPostBack feature in ASP.NET?
AutoPostBack allows a control to automatically postback when an event is fired. For eg: If we have a Button control and want the event to be posted to the server for processing, we can set AutoPostBack = True on the button.
How do you disable AutoPostBack?
Hence the AutoPostBack can be disabled on an ASP.NET page by disabling AutoPostBack on all the controls of a page. AutoPostBack is caused by a control on the page.
What are the different code models available in ASP.NET 2.0?
There are 2 code models available in ASP.NET 2.0. One is the single-file page and the other one is the code behind page.
Which base class does the web form inherit from?
Page class in the System.Web.UI namespace.
Which are the new special folders that are introduced in ASP.NET 2.0?
There are seven new folders introduced in ASP.NET 2.0 :

\App_Browsers folder – Holds browser definitions(.brower) files which identify the browser and their capabilities.
\App_Code folder – Contains source code (.cs, .vb) files which are automatically compiled when placed in this folder. Additionally placing web service files generates a proxy class(out of .wsdl) and a typed dataset (out of .xsd).
\App_Data folder – Contains data store files like .mdf (Sql Express files), .mdb, XML files etc. This folder also stores the local db to maintain membership and role information.
\App_GlobalResources folder – Contains assembly resource files (.resx) which when placed in this folder are compiled automatically. In earlier versions, we were required to manually use the resgen.exe tool to compile resource files. These files can be accessed globally in the application.
\App_LocalResources folder – Contains assembly resource files (.resx) which can be used by a specific page or control.
\App_Themes folder – This folder contains .css and .skin files that define the appearance of web pages and controls.
\App_WebReferences folder – Replaces the previously used Web References folder. This folder contains the .disco, .wsdl, .xsd files that get generated when accessing remote web services.
Explain the ViewState in ASP.NET?
Http is a stateless protocol. Hence the state of controls is not saved between postbacks. Viewstate is the means of storing the state of server side controls between postbacks. The information is stored in HTML hidden fields. In other words, it is a snapshot of the contents of a page.
You can disable viewstate by a control by setting the EnableViewState property to false.
What does the EnableViewState property signify?
EnableViewState saves the state of an object in a page between postbacks. Objects are saved in a Base64 encoded string. If you do not need to store the page, turn it off as it adds to the page size.
There is an excellent article by Peter Bromberg to understand Viewstate in depth.





Explain the ASP.NET Page Directives?
Page directives configure the runtime environment that will execute the page. The complete list of directives is as follows:
@ Assembly - Links an assembly to the current page or user control declaratively.
@ Control - Defines control-specific attributes used by the ASP.NET page parser and compiler and can be included only in .ascx files (user controls).
@ Implements - Indicates that a page or user control implements a specified .NET Framework interface declaratively.
@ Import - Imports a namespace into a page or user control explicitly.
@ Master - Identifies a page as a master page and defines attributes used by the ASP.NET page parser and compiler and can be included only in .master files.
@ MasterType - Defines the class or virtual path used to type the Master property of a page.
@ OutputCache - Controls the output caching policies of a page or user control declaratively.
@ Page - Defines page-specific attributes used by the ASP.NET page parser and compiler and can be included only in .aspx files.
@ PreviousPageType - Creates a strongly typed reference to the source page from the target of a cross-page posting.
@ Reference - Links a page, user control, or COM control to the current page or user control declaratively.
@ Register - Associates aliases with namespaces and classes, which allow user controls and custom server controls to be rendered when included in a requested page or user control.
This list has been taken from here.
Explain the Validation Controls used in ASP.NET 2.0?
Validation controls allows you to validate a control against a set of rules. There are 6 different validation controls used in ASP.NET 2.0.
RequiredFieldValidator – Checks if the control is not empty when the form is submitted.
CompareValidator – Compares the value of one control to another using a comparison operator (equal, less than, greater than etc).
RangeValidator – Checks whether a value falls within a given range of number, date or string.
RegularExpressionValidator – Confirms that the value of a control matches a pattern defined by a regular expression. Eg: Email validation.
CustomValidator – Calls your own custom validation logic to perform validations that cannot be handled by the built in validators.
ValidationSummary – Show a summary of errors raised by each control on the page on a specific spot or in a message box.
How do you identify that the page is post back?
By checking the IsPostBack property. If IsPostBack is true, the page has been posted back.
What are Master Pages?
Master pages is a template that is used to create web pages with a consistent layout throughout your application. Master Pages contains content placeholders to hold page specific content. When a page is requested, the contents of a Master page are merged with the content page, thereby giving a consistent layout.
How is a Master Page different from an ASP.NET page?
The MasterPage has a @Master top directive and contains ContentPlaceHolder server controls. It is quiet similar to an ASP.NET page.






How do you attach an exisiting page to a Master page?
By using the MasterPageFile attribute in the @Page directive and removing some markup.
How do you set the title of an ASP.NET page that is attached to a Master Page?
By using the Title property of the @Page directive in the content page. Eg:
<@Page MasterPageFile="Sample.master" Title="I hold content" %>
What is a nested master page? How do you create them?
A Nested master page is a master page associated with another master page. To create a nested master page, set the MasterPageFile attribute of the @Master directive to the name of the .master file of the base master page.
What are Themes?
Themes are a collection of CSS files, .skin files, and images. They are text based style definitions and are very similar to CSS, in that they provide a common look and feel throughout the website.
What are skins?
A theme contains one or more skin files. A skin is simply a text file with a .skin extension and contains definition of styles applied to server controls in an ASP.NET page. For eg:

Defines a skin that will be applied to all buttons throughout to give it a consistent look and feel.
What is the difference between Skins and Css files?
Css is applied to HTML controls whereas skins are applied to server controls.
What is a User Control?
User controls are reusable controls, similar to web pages. They cannot be accessed directly.
Explain briefly the steps in creating a user control?
 Create a file with .ascx extension and place the @Control directive at top of the page.
 Included the user control in a Web Forms page using a @Register directive
What is a Custom Control?
Custom controls are compiled components that run on the server and that encapsulate user-interface and other related functionality into reusable packages. They can include all the design-time features of standard ASP.NET server controls, including full support for Visual Studio design features such as the Properties window, the visual designer, and the Toolbox.
What are the differences between user and custom controls?
User controls are easier to create in comparison to custom controls, however user controls can be less convenient to use in advanced scenarios.
User controls have limited support for consumers who use a visual design tool whereas custom controls have full visual design tool support for consumers.
A separate copy of the user control is required in each application that uses it whereas only a single copy of the custom control is required, in the global assembly cache, which makes maintenance easier.
A user control cannot be added to the Toolbox in Visual Studio whereas custom controls can be added to the Toolbox in Visual Studio.
User controls are good for static layout whereas custom controls are good for dynamic layout.
Where do you store your connection string information?
The connection string can be stored in configuration files (web.config).









What is the difference between ‘Web.config’ and ‘Machine.config’?
Web.config files are used to apply configuration settings to a particular web application whereas machine.config file is used to apply configuration settings for all the websites on a web server.
Web.config files are located in the application's root directory or inside a folder situated in a lower hierarchy. The machine.config is located in the Windows directory Microsoft.Net\Framework\Version\CONFIG.
There can be multiple web.config files in an application nested at different hierarchies. However there can be only one machine.config file on a web server.
What is the difference between Server.Transfer and Response.Redirect?
Response. Redirect involves a roundtrip to the server whereas Server.Transfer conserves server resources by avoiding the roundtrip. It just changes the focus of the web server to a different page and transfers the page processing to a different page.
Response. Redirect can be used for both .aspx and html pages whereas Server.Transfer can be used only for .aspx pages.
Response. Redirect can be used to redirect a user to an external websites. Server.Transfer can be used only on sites running on the same server. You cannot use Server.Transfer to redirect the user to a page running on a different server.
Response.Redirect changes the url in the browser. So they can be bookmarked. Whereas Server.Transfer retains the original url in the browser. It just replaces the contents of the previous page with the new one.
What method do you use to explicitly kill a users session?
Session. Abandon ().
What is a web service?
Web Services are applications delivered as a service on the Web. Web services allow for programmatic access of business logic over the Web. Web services typically rely on XML-based protocols, messages, and interface descriptions for communication and access. Web services are designed to be used by other programs or applications rather than directly by end user. Programs invoking a Web service are called clients. SOAP over HTTP is the most commonly used protocol for invoking Web services
What is XHTML? Are ASP.NET Pages compliant with XHTML?
In simple words, XHTML is a stricter and cleaner version of HTML. XHTML stands for EXtensible Hypertext Markup Language and is a W3C Recommendation.
Yes, ASP.NET 2.0 Pages are XHTML compliant. However the freedom has been given to the user to include the appropriate document type declaration.
More info can be found at http://msdn2.microsoft.com/en-us/library/exc57y7e.aspx
Can I deploy the application without deploying the source code on the server?
Yes. You can obfuscate your code by using a new precompilation process called ‘precompilation for deployment’. You can use the aspnet_compiler.exe to precompile a site. This process builds each page in your web application into a single application DLL and some placeholder files. These files can then be deployed to the server.
You can also accomplish the same task using Visual Studio 2005 by using the Build->Publish menu.






Does ViewState affect performance? What is the ideal size of a ViewState? How can you compress a viewstate?
Viewstate stores the state of controls in HTML hidden fields. At times, this information can grow in size. This does affect the overall responsiveness of the page, thereby affecting performance. The ideal size of a viewstate should be not more than 25-30% of the page size.
Viewstate can be compressed to almost 50% of its size. .NET also provides the GZipStream or DeflateStream to compress viewstate. Another option is explained by Scott Hanselmann over here.
How can you detect if a view state has been tampered?
By setting the EnableViewStateMac to true in the @Page directive. This attribute checks the encoded and encrypted view state for tampering.
Can I use different programming languages in the same application?
Yes. Each page can be written with a different programming language in the same application. You can create a few pages in C# and a few in VB.NET.
Can the App_Code folder contain source code files in different programming languages?
No. All source code files kept in the App_Code folder must be in the same programming language.
How do you secure your connection string information?
By using the Protected Configuration feature.
How do you secure your configuration files to be accessed remotely by unauthorized users?
ASP.NET configures IIS to deny access to any user that requests access to the Machine.config or Web.config files.
How can I configure ASP.NET applications that are running on a remote machine?
You can use the Web Site Administration Tool to configure remote websites.
How many web.config files can I have in an application?
You can keep multiple web.config files in an application. You can place a Web.config file inside a folder or wherever you need (apart from some exceptions) to override the configuration settings that are inherited from a configuration file located at a higher level in the hierarchy.
I have created a configuration setting in my web.config and have kept it at the root level. How do I prevent it from being overridden by another web.config that appears lower in the hierarchy?
By setting the element's Override attribute to false.
What is the difference between Response.Write and Response.Output.Write?
As quoted by Scott Hanselman, the short answer is that the latter gives you String. Format-style output and the former don’t.
To get a detailed explanation, follow this link.
What is Cross Page Posting? How is it done?
By default, ASP.NET submits a form to the same page. In cross-page posting, the form is submitted to a different page. This is done by setting the ‘PostBackUrl’ property of the button (that causes postback) to the desired page. In the code-behind of the page to which the form has been posted, use the ‘FindControl’ method of the ‘PreviousPage’ property to reference the data of the control in the first page.
Can you change a Master Page dynamically at runtime? How?
Yes. To change a master page, set the MasterPageFile property to point to the .master page during the PreInit page event.






How do you apply Themes to an entire application?
By specifying the theme in the web.config file.
Eg:





How do you exclude an ASP.NET page from using Themes?
To remove themes from your page, use the EnableTheming attribute of the Page directive.
Your client complains that he has a large form that collects user input. He wants to break the form into sections, keeping the information in the forms related. Which control will you use?
The ASP.NET Wizard Control.
To learn more about this control, visit this link.
Do web services support data reader?
No. However it does support a dataset.
What is use of the AutoEventWireup attribute in the Page directive?
The AutoEventWireUp is a Boolean attribute that allows automatic wire up of page events when this attribute is set to true on the page. It is set to true by default for a C# web form whereas it is set as False for VB.NET forms. Pages developed with Visual Studio .NET have this attribute set to false, and page events are individually tied to handlers.
What happens when you change the web.config file at run time?
ASP.NET invalidates the existing cache and assembles a new cache. Then ASP.NET automatically restarts the application to apply the changes.
Can you programmatically access IIS configuration settings?
Yes. You can use ADSI, WMI, or COM interfaces to configure IIS programmatically.
How does Application Pools work in IIS 6.0?
As explained under the IIS documentation, when you run IIS 6.0 in worker process isolation mode, you can separate different Web applications and Web sites into groups known as application pools. An application pool is a group of one or more URLs that are served by a worker process or set of worker processes. Any Web directory or virtual directory can be assigned to an application pool.

Every application within an application pool shares the same worker process. Because each worker process operates as a separate instance of the worker process executable, W3wp.exe, the worker process that services one application pool is separated from the worker process that services another. Each separate worker process provides a process boundary so that when an application is assigned to one application pool, problems in other application pools do not affect the application. This ensures that if a worker process fails, it does not affect the applications running in other application pools.

Use multiple application pools when you want to help ensure that applications and Web sites are confidential and secure. For example, an enterprise organization might place its human resources Web site and its finance Web site on the same server, but in different application pools. Likewise, an ISP that hosts Web sites and applications for competing companies might run each companys Web services on the same server, but in different application pools. Using different application pools to isolate applications helps prevent one customer from accessing, changing, or using confidential information from another customer’s site.
In HTTP.sys, an application pool is represented by a request queue, from which the user-mode worker processes that service an application pool collect the requests. Each pool can manage requests for one or more unique Web applications, which you assign to the application pool based on their URLs. Application pools, then, are essentially worker process configurations that service groups of namespaces.
Multiple application pools can operate at the same time. An application, as defined by its URL, can only be served by one application pool at any time. While one application pool is servicing a request, you cannot route the request to another application pool. However, you can assign applications to another application pool while the server is running.
What is an application server?
As defined in Wikipedia, an application server is a software engine that delivers applications to client computers or devices. The application server runs your server code. Some well known application servers are IIS (Microsoft), Web Logic Server (BEA), JBoss (Red Hat), Web Sphere (IBM).
Compare C# and VB.NET
A detailed comparison can be found over here.
What is a base class and derived class?
A class is a template for creating an object. The class from which other classes derive fundamental functionality is called a base class. For e.g. If Class Y derives from Class X, then Class X is a base class.

The class which derives functionality from a base class is called a derived class. If Class Y derives from Class X, then Class Y is a derived class.
What is an extender class?
An extender class allows you to extend the functionality of an existing control. It is used in Windows forms applications to add properties to controls.
A demonstration of extender classes can be found over here.
What is inheritance?
Inheritance represents the relationship between two classes where one type derives functionality from a second type and then extends it by adding new methods, properties, events, fields and constants.

C# support two types of inheritance:
 Implementation inheritance
 Interface inheritance
What is implementation and interface inheritance?
When a class (type) is derived from another class (type) such that it inherits all the members of the base type it is Implementation Inheritance.
When a type (class or a struct) inherits only the signatures of the functions from another type it is Interface Inheritance.
In general Classes can be derived from another class, hence support Implementation inheritance. At the same time Classes can also be derived from one or more interfaces. Hence they support Interface inheritance.
Source: Exforsys.
What is inheritance hierarchy?
The class which derives functionality from a base class is called a derived class. A derived class can also act as a base class for another class. Thus it is possible to create a tree-like structure that illustrates the relationship between all related classes. This structure is known as the inheritance hierarchy.



How do you prevent a class from being inherited?
In VB.NET you use the NotInheritable modifier to prevent programmers from using the class as a base class. In C#, use the sealed keyword.
When should you use inheritance?
Read this.
Define Overriding?
Overriding is a concept where a method in a derived class uses the same name, return type, and arguments as a method in its base class. In other words, if the derived class contains its own implementation of the method rather than using the method in the base class, the process is called overriding.
Can you use multiple inheritance in .NET?
.NET supports only single inheritance. However the purpose is accomplished using multiple interfaces.
Why don’t we have multiple inheritance in .NET?
There are several reasons for this. In simple words, the efforts are more, benefits are less. Different languages have different implementation requirements of multiple inheritance. So in order to implement multiple inheritance, we need to study the implementation aspects of all the languages that are CLR compliant and then implement a common methodology of implementing it. This is too much of efforts. Moreover multiple interface inheritance very much covers the benefits that multiple inheritance has.
What is an Interface?
An interface is a standard or contract that contains only the signatures of methods or events. The implementation is done in the class that inherits from this interface. Interfaces are primarily used to set a common standard or contract.
When should you use abstract class vs. interface or what is the difference between an abstract class and interface?
I would suggest you to read this. There is a good comparison given over here.
What are events and delegates?
An event is a message sent by a control to notify the occurrence of an action. However it is not known which object receives the event. For this reason, .NET provides a special type called Delegate which acts as an intermediary between the sender object and receiver object.
What is business logic?
It is the functionality which handles the exchange of information between database and a user interface.
What is a component?
Component is a group of logically related classes and methods. A component is a class that implements the IComponent interface or uses a class that implements IComponent interface.
What is a control?
A control is a component that provides user-interface (UI) capabilities.
What are the differences between a control and a component?
The differences can be studied over here.
What are design patterns?
Design patterns are common solutions to common design problems.
What is a connection pool?
A connection pool is a ‘collection of connections’ which are shared between the clients requesting one. Once the connection is closed, it returns back to the pool. This allows the connections to be reused.
What is a flat file?
A flat file is the name given to text, which can be read or written only sequentially.


What are functional and non-functional requirements?
Functional requirements define the behavior of a system whereas non-functional requirements specify how the system should behave; in other words they specify the quality requirements and judge the behavior of a system.
E.g.
Functional - Display a chart which shows the maximum number of products sold in a region.
Non-functional – The data presented in the chart must be updated every 5 minutes.
What is the global assembly cache (GAC)?
GAC is a machine-wide cache of assemblies that allows .NET applications to share libraries. GAC solves some of the problems associated with dll’s (DLL Hell).
What is a stack? What is a heap? Give the differences between the two?
Stack is a place in the memory where value types are stored. Heap is a place in the memory where the reference types are stored.

Check this link for the differences.
What is instrumentation?
It is the ability to monitor an application so that information about the application’s progress, performance and status can be captured and reported.
What is code review?
The process of examining the source code generally through a peer, to verify it against best practices.
What is logging?
Logging is the process of persisting information about the status of an application.
What are mock-ups?
Mock-ups are a set of designs in the form of screens, diagrams, snapshots etc., that helps verify the design and acquire feedback about the application’s requirements and use cases, at an early stage of the design process.
What is a Form?
A form is a representation of any window displayed in your application. Form can be used to create standard, borderless, floating, modal windows.
What is a multiple-document interface (MDI)?
A user interface container that enables a user to work with more than one document at a time. E.g. Microsoft Excel.
What is a single-document interface (SDI)?
A user interface that is created to manage graphical user interfaces and controls into single windows. E.g. Microsoft Word
What is BLOB?
A BLOB (binary large object) is a large item such as an image or an exe represented in binary form.

What is ClickOnce?
ClickOnce is a new deployment technology that allows you to create and publish self-updating applications that can be installed and run with minimal user interaction.
What is object role modeling (ORM)?
It is a logical model for designing and querying database models. There are various ORM tools in the market like Case Talk, Microsoft Visio for Enterprise Architects, Infagon etc.
What is a private assembly?
A private assembly is local to the installation directory of an application and is used only by that application.

What is a shared assembly?
A shared assembly is kept in the global assembly cache (GAC) and can be used by one or more applications on a machine.
What is the difference between user and custom controls?
User controls are easier to create whereas custom controls require extra effort.
User controls are used when the layout is static whereas custom controls are used in dynamic layouts.
A user control cannot be added to the toolbox whereas a custom control can be.
A separate copy of a user control is required in every application that uses it whereas since custom controls are stored in the GAC, only a single copy can be used by all applications.
Where do custom controls reside?
In the global assembly cache (GAC).
What is a third-party control?
A third-party control is one that is not created by the owners of a project. They are usually used to save time and resources and reuse the functionality developed by others (third-party).
What is a binary formatter?
Binary formatter is used to serialize and deserialize an object in binary format.
What is Boxing/Unboxing?
Boxing is used to convert value types to object.
E.g. int x = 1;
Object obj = x;
Unboxing is used to convert the object back to the value type.
E.g. int y = (int) obj;
Boxing/Unboxing is quiet an expensive operation.

What is a COM Callable Wrapper (CCW)?
CCW is a wrapper created by the common language runtime (CLR) that enables COM components to access .NET objects.

What is a Runtime Callable Wrapper (RCW)?
RCW is a wrapper created by the common language runtime (CLR) to enable .NET components to call COM components.

What is a digital signature?
A digital signature is an electronic signature used to verify/guarantee the identity of the individual who is sending the message.

What is garbage collection?
Garbage collection is the process of managing the allocation and release of memory in your applications. Read this article for more information.

What is globalization?
Globalization is the process of customizing applications that support multiple cultures and regions.

What is localization?
Localization is the process of customizing applications that support a given culture and regions.

What is MIME?
The definition of MIME or Multipurpose Internet Mail Extensions as stated in MSDN is “MIME is a standard that can be used to include content of various types in a single message. MIME extends the Simple Mail Transfer Protocol (SMTP) format of mail messages to include multiple content, both textual and non-textual. Parts of the message may be images, audio, or text in different character sets. The MIME standard derives from RFCs such as 2821 and 2822”.

Deleting Multiple Rows in a Grid View

If you have used Hotmail or any other similar email client, you might have observed that we have the option of selecting multiple rows (using the checkbox provided) and perform a set of operations on them. In this article, we will replicate this scenario for a GridView. A GridView allows us to delete only a single row at a time. We will extend this functionality to select multiple rows and delete all of the selected rows in a single stroke. In this article, I assume that you are aware of creating asp.net web applications and have worked with GridView.
The sample makes use of the Northwind database. We will be pulling data from the Employee table. For this sample to work, drop all the Foreign Key relationships on the Employee Table. To do so, in Sql Server Management Studio, browse to the Northwind database and open the Employee table in design view. Right click in the Table designer on the right hand side and choose ‘Relationships’. Select all the relationships like FK_Orders_Employees, FK_EmployeeTerritories_Employees etc and delete them. This step is necessary as we will get a constraint violation exception if we do not do so.
Once we are through with the task of removing the relationships in the Employee table, let us explore the steps to create a GridView with functionality to delete multiple rows at a time.
Perform the following steps:
Step 1: Create an .aspx page and add a GridView and a SqlDataSource control to it.
Step 2: Configure the connection of SqlDataSource to point to the Northwind database. Create queries for the Select and Delete commands. The resultant code will look similar as given below :
SelectCommand="SELECT EmployeeID, LastName, City FROM Employees"
DeleteCommand="DELETE FROM Employees WHERE [EmployeeID] = @EmployeeID"
ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>" >




Step 3: Once the SqlDataSource has been configured, bind the gridview with this data source.
Step 4: To create a checkbox in each row, follow these steps:
1. Create a TemplateField inside the to add custom content to each column.
2. Inside the TemplateField, create an ItemTemplate with a CheckBox added to it.





This will add a checkbox to each row in the grid.




Step 5: Add a button control, and rename it to btnMultipleRowDelete.
The resultant markup in the design view will look similar to the code below :















SelectCommand="SELECT EmployeeID, LastName, City FROM Employees"
DeleteCommand="DELETE FROM Employees WHERE [EmployeeID] = @EmployeeID"
ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>" >





ID="btnMultipleRowDelete"
OnClick="btnMultipleRowDelete_Click"
runat="server"
Text="Delete Rows" />

In Code behind file (.cs), code the button click event. Our code will first loop through all the rows in the GridView. If a row is checked, the code retrieves the EmployeeID and passes the selected value to the Delete Command.




protected void btnMultipleRowDelete_Click(object sender, EventArgs e)
{
// Looping through all the rows in the GridView
foreach (GridViewRow row in GridView1.Rows)
{
CheckBox checkbox = (CheckBox)row.FindControl("cbRows");

//Check if the checkbox is checked.
//value in the HtmlInputCheckBox's Value property is set as the //value of the delete command's parameter.
if (checkbox.Checked)
{
// Retreive the Employee ID
int employeeID = Convert.ToInt32(GridView1.DataKeys[row.RowIndex].Value);
// Pass the value of the selected Employye ID to the Delete //command.
SqlDataSource1.DeleteParameters["EmployeeID"].DefaultValue = employeeID.ToString();
SqlDataSource1.Delete();
}
}
}

Run the code, and select a few rows in the grid. On clicking the ‘Delete Rows’ button, the selected rows get deleted.

Rather than deleting rows one at a time, deleting them in a batch is a good practice. I would encourage you to read Scott Mitchell’s article for the same.

Conclusion

By default, the gridview provides the functionality to delete a single row at a time. In this article, we explored how to extend the functionality of the grid view and delete multiple rows. I hope this article was useful and I thank you for viewing it.
Sending Email In ASP.NET 2.0
In ASP.NET, sending emails has become simpler. The classes required to send an email are contained in the System.Net.Mail. The steps required to send an email from ASP.NET are as follows :
Step 1: Declare the System.Net.Mail namespace
using System.Net.Mail;
Step 2: Create a MailMessage object. This class contains the actual message you want to send. There are four overloaded constructors provided in this class. We will be using
public MailMessage ( string from, string to, string subject, string body )
The constructor of this MailMessage class is used to specify the sender email, receiver email, subject, body.
MailMessage message = new MailMessage ("abc@somedomain.com","administrator@anotherdomain.com","Testing","This is a test mail");

Step 3: To add an attachment to the message, use the Attachment class.

string fileAttach = Server.MapPath("myEmails") + "\\Mypic.jpg";
Attachment attach = new Attachment(fileAttach);
message.Attachments.Add(attach);

Step 4:After creating a message, use the SmtpClient to send the email to the specified SMTP server. I will be using ‘localhost’ as the SMTP server.

SmtpClient client = new SmtpClient("localhost");
client.Send(message);

Additionally, if required, you

client.Timeout = 500;
// Pass the credentials if the server requires the client to authenticate before it will send e-mail on the client's behalf.
client.Credentials = CredentialCache.DefaultNetworkCredentials;

That’s it. It’s that simple.
To configure SMTP configuration data for ASP.NET, you would add the following tags to your web.config file.









References :
http://msdn2.microsoft.com/En-US/library/system.net.mail.mailmessage.aspx

Conclusion:

In this short article, we explored how easy it is to send Email’s with attachments using the classes in System.Net.Mail. This approach of sending mails will remain the same for web as well as windows application.





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