Asp.net real time MVC Interview Quesitons with answers

What is MVC?

MVC is a framework methodology that divides an application’s implementation into three component roles: models, views, and controllers.

“Models” in a MVC based application are the components of the application that are responsible for maintaining state. Often this state is persisted inside a database (for example: we might have a Product class that is used to represent order data from the Products table inside SQL).
“Views” in a MVC based application are the components responsible for displaying the application’s user interface. Typically this UI is created off of the model data (for example: we might create an Product “Edit” view that surfaces textboxes, dropdowns and checkboxes based on the current state of a Product object).
“Controllers” in a MVC based application are the components responsible for handling end user interaction, manipulating the model, and ultimately choosing a view to render to display UI. In a MVC application the view is only about displaying information – it is the controller that handles and responds to user input and interaction.

What are the 3 main components of an ASP.NET MVC application?
1. M - Model
2. V - View
3. C - Controller

In which assembly is the MVC framework defined?
System.Web.Mvc

Is it possible to combine ASP.NET webforms and ASP.MVC and develop a single web application?
Yes, it is possible to combine ASP.NET webforms and ASP.MVC and develop a single web application.

What does Model, View and Controller represent in an MVC application?
Model: Model represents the application data domain. In short the applications business logic is contained with in the model.

View: Views represent the user interface, with which the end users interact. In short the all the user interface logic is contained with in the UI.

Controller: Controller is the component that responds to user actions. Based on the user actions, the respective controller, work with the model, and selects a view to render that displays the user interface. The user input logic is contained with in the controller.

What is the greatest advantage of using asp.net mvc over asp.net webforms?
It is difficult to unit test UI with webforms, where views in mvc can be very easily unit tested.

Which approach provides better support for test driven development - ASP.NET MVC or ASP.NET Webforms?
ASP.NET MVC
What is Razor View Engine?

Razor view engine is a new view engine created with ASP.Net MVC model using specially designed Razor parser to render the HTML out of dynamic server side code. It allows us to write Compact, Expressive, Clean and Fluid code with new syntaxes to include server side code in to HTML.

What are the advantages of ASP.NET MVC?
1. Extensive support for TDD. With asp.net MVC, views can also be very easily unit tested.
2. Complex applications can be easily managed
3. Seperation of concerns. Different aspects of the application can be divided into Model, View and Controller.
4. ASP.NET MVC views are light weight, as they donot use viewstate.

Is it possible to unit test an MVC application without running the controllers in an ASP.NET process?
Yes, all the features in an asp.net MVC application are interface based and hence mocking is much easier. So, we don't have to run the controllers in an ASP.NET process for unit testing.
What is namespace of asp.net mvc?

ASP.NET MVC namespaces and classes are located in the System.Web.Mvc assembly.

System.Web.Mvc namespace 
Contains classes and interfaces that support the MVC pattern for ASP.NET Web applications. This namespace includes classes that represent controllers, controller factories, action results, views, partial views, and model binders.

System.Web.Mvc.Ajax namespace 
Contains classes that support Ajax scripts in an ASP.NET MVC application. The namespace includes support for Ajax scripts and Ajax option settings.

System.Web.Mvc.Async namespace 
Contains classes and interfaces that support asynchronous actions in an ASP.NET MVC application

System.Web.Mvc.Html namespace 
Contains classes that help render HTML controls in an MVC application. The namespace includes classes that support forms, input controls, links, partial views, and validation.

Is it possible to share a view across multiple controllers?
Yes, put the view into the shared folder. This will automatically make the view available across multiple controllers.

What is the role of a controller in an MVC application?
The controller responds to user interactions, with the application, by selecting the action method to execute and alse selecting the view to render.

Where are the routing rules defined in an asp.net MVC application?
In Application_Start event in Global.asax

Name a few different return types of a controller action method?
The following are just a few return types of a controller action method. In general an action method can return an instance of a any class that derives from ActionResult class.
1. ViewResult
2. JavaScriptResult
3. RedirectResult
4. ContentResult
5. JsonResult
What is the ‘page lifecycle’ of an ASP.NET MVC?

Following process are performed by ASP.Net MVC page:
1) App initialization
2) Routing
3) Instantiate and execute controller
4) Locate and invoke controller action
5) Instantiate and render view

What is the significance of NonActionAttribute?
In general, all public methods of a controller class are treated as action methods. If you want prevent this default behaviour, just decorate the public method with NonActionAttribute.

What is the significance of ASP.NET routing?
ASP.NET MVC uses ASP.NET routing, to map incoming browser requests to controller action methods. ASP.NET Routing makes use of route table. Route table is created when your web application first starts. The route table is present in the Global.asax file.
How route table is created in ASP.NET MVC?

When an MVC application first starts, the Application_Start() method is called. This method, in turn, calls the RegisterRoutes() method. The RegisterRoutes() method creates the route table.

What are the 3 segments of the default route, that is present in an ASP.NET MVC application?
1st Segment - Controller Name
2nd Segment - Action Method Name
3rd Segment - Parameter that is passed to the action method

Examplehttp://nareshkamuni.blogspot.in/search/label/MVC
Controller Name = search
Action Method Name = label
Parameter Id = MVC

ASP.NET MVC application, makes use of settings at 2 places for routing to work correctly. What are these 2 places?
1. Web.Config File : ASP.NET routing has to be enabled here.
2. Global.asax File : The Route table is created in the application Start event handler, of the Global.asax file.
How do you avoid XSS Vulnerabilities in ASP.NET MVC?

Use thesyntax in ASP.NET MVC instead of usingin .net framework 4.0.

What is the adavantage of using ASP.NET routing?
In an ASP.NET web application that does not make use of routing, an incoming browser request should map to a physical file. If the file does not exist, we get page not found error.

An ASP.NET web application that does make use of routing, makes use of URLs that do not have to map to specific files in a Web site. Because the URL does not have to map to a file, you can use URLs that are descriptive of the user's action and therefore are more easily understood by users.

What are the 3 things that are needed to specify a route?
1. URL Pattern - You can include placeholders in a URL pattern so that variable data can be passed to the request handler without requiring a query string.
2. Handler - The handler can be a physical file such as an .aspx file or a controller class.
3. Name for the Route - Name is optional.

Is the following route definition a valid route definition?
{controller}{action}/{id}
No, the above definition is not a valid route definition, because there is no literal value or delimiter between the placeholders. Therefore, routing cannot determine where to separate the value for the controller placeholder from the value for the action placeholder.

What is the use of the following default route?
{resource}.axd/{*pathInfo}
This route definition, prevent requests for the Web resource files such as WebResource.axd or ScriptResource.axd from being passed to a controller.

What is the difference between adding routes, to a webforms application and to an mvc application?
To add routes to a webforms application, we use MapPageRoute() method of the RouteCollection class, where as to add routes to an MVC application we use MapRoute() method.

How do you handle variable number of segments in a route definition?
Use a route with a catch-all parameter. An example is shown below. * is referred to as catch-all parameter.
controller/{action}/{*parametervalues}

What are the 2 ways of adding constraints to a route?
1. Use regular expressions
2. Use an object that implements IRouteConstraint interface

Give 2 examples for scenarios when routing is not applied?
1. A Physical File is Found that Matches the URL Pattern - This default behaviour can be overriden by setting the RouteExistingFiles property of the RouteCollection object to true.
2. Routing Is Explicitly Disabled for a URL Pattern - Use the RouteCollection.Ignore() method to prevent routing from handling certain requests.

What is the use of action filters in an MVC application?
Action Filters allow us to add pre-action and post-action behavior to controller action methods.

If I have multiple filters impleted, what is the order in which these filters get executed?
1. Authorization filters
2. Action filters
3. Response filters
4. Exception filters

What are the different types of filters, in an asp.net mvc application?
1. Authorization filters
2. Action filters
3. Result filters
4. Exception filters

Give an example for Authorization filters in an asp.net mvc application?
1. RequireHttpsAttribute
2. AuthorizeAttribute

Which filter executes first in an asp.net mvc application?
Authorization filter


What are the levels at which filters can be applied in an asp.net mvc application?
1. Action Method
2. Controller
3. Application
[b]Is it possible to create a custom filter?[/b]
Yes

What filters are executed in the end?
Exception Filters

Is it possible to cancel filter execution?
Yes

What type of filter does OutputCacheAttribute class represents?
Result Filter

What are the 2 popular asp.net mvc view engines?
1. Razor
2. .aspx
What is difference between Viewbag and Viewdata in ASP.NET MVC?

The basic difference between ViewData and ViewBag is that in ViewData instead creating dynamic properties we use properties of Model to transport the Model data in View and in ViewBag we can create dynamic properties without using Model data.

What symbol would you use to denote, the start of a code block in razor views?
@

What symbol would you use to denote, the start of a code block in aspx views?
<%= %>

In razor syntax, what is the escape sequence character for @ symbol?
The escape sequence character for @ symbol, is another @ symbol

When using razor views, do you have to take any special steps to proctect your asp.net mvc application from cross site scripting (XSS) attacks?
No, by default content emitted using a @ block is automatically HTML encoded to protect from cross site scripting (XSS) attacks.

When using aspx view engine, to have a consistent look and feel, across all pages of the application, we can make use of asp.net master pages. What is asp.net master pages equivalent, when using razor views?
To have a consistent look and feel when using razor views, we can make use of layout pages. Layout pages, reside in the shared folder, and are named as _Layout.cshtml

What are sections?
Layout pages, can define sections, which can then be overriden by specific views making use of the layout. Defining and overriding sections is optional.

What are the file extensions for razor views?
1. .cshtml - If the programming lanugaue is C#
2. .vbhtml - If the programming lanugaue is VB

How do you specify comments using razor syntax?
Razor syntax makes use of @* to indicate the begining of a comment and *@ to indicate the end. An example is shown below.

What is Routing?

A route is a URL pattern that is mapped to a handler. The handler can be a physical file, such as an .aspx file in a Web Forms application. Routing module is responsible for mapping incoming browser requests to particular MVC controller actions.

WCF Interview Questions With Answers for 1 year Experience

What is WCF?

Windows Communication Foundation (WCF) is an SDK for developing and deploying services on Windows. WCF provides a runtime environment for services, enabling you to expose CLR types as services, and to consume other services as CLR types.

WCF is part of .NET 3.0 and requires .NET 2.0, so it can only run on systems that support it.

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.

What is address in WCF and how many types of transport schemas are there in WCF?

Address is a way of letting client know that where a service is located. In WCF, every service is associated with a unique address. This contains the location of the service and transport schemas.

WCF supports following transport schemas

HTTP
TCP
Peer network
IPC (Inter-Process Communication over named pipes)
MSMQ

The sample address for above transport schema may look like

http://localhost:81
http://localhost:81/MyService
net.tcp://localhost:82/MyService
net.pipe://localhost/MyPipeService
net.msmq://localhost/private/MyMsMqService
net.msmq://localhost/MyMsMqService

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.

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)

What is binding and how many types of bindings are there in WCF?

A binding defines how an endpoint communicates to the world. A binding defines the transport (such as HTTP or TCP) and the encoding being used (such as text or binary). A binding can contain binding elements that specify details like the security mechanisms used to secure messages, or the message pattern used by an endpoint.

WCF supports nine types of bindings.

Basic binding

Offered by the BasicHttpBinding class, this is designed to expose a WCF service as a legacy ASMX web service, so that old clients can work with new services. When used by the client, this binding enables new WCF clients to work with old ASMX services.

TCP binding

Offered by the NetTcpBinding class, this uses TCP for cross-machine communication on the intranet. It supports a variety of features, including reliability, transactions, and security, and is optimized for WCF-to-WCF communication. As a result, it requires both the client and the service to use WCF.


Peer network binding

Offered by the NetPeerTcpBinding class, this uses peer networking as a transport. The peer network-enabled client and services all subscribe to the same grid and broadcast messages to it.


IPC binding

Offered by the NetNamedPipeBinding class, this uses named pipes as a transport for same-machine communication. It is the most secure binding since it cannot accept calls from outside the machine and it supports a variety of features similar to the TCP binding.


Web Service (WS) binding

Offered by the WSHttpBinding class, this uses HTTP or HTTPS for transport, and is designed to offer a variety of features such as reliability, transactions, and security over the Internet.


Federated WS binding

Offered by the WSFederationHttpBinding class, this is a specialization of the WS binding, offering support for federated security.


Duplex WS binding

Offered by the WSDualHttpBinding class, this is similar to the WS binding except it also supports bidirectional communication from the service to the client.


MSMQ binding

Offered by the NetMsmqBinding class, this uses MSMQ for transport and is designed to offer support for disconnected queued calls.


MSMQ integration binding

Offered by the MsmqIntegrationBinding class, this converts WCF messages to and from MSMQ messages, and is designed to interoperate with legacy MSMQ clients.

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.

How to define a service as REST based service in WCF?

WCF 3.5 provides explicit support for RESTful communication using a new binding named WebHttpBinding.
The below code shows how to expose a RESTful service

[ServiceContract]
interface IStock
{
[OperationContract]
[WebGet]
int GetStock(string StockId);
}

By adding the WebGetAttribute, we can define a service as REST based service that can be accessible using HTTP GET operation.

What is the address formats of the WCF transport schemas?

Address format of WCF transport schema always follow

[transport]://[machine or domain][:optional port] format.

for example:

HTTP Address Format

http://localhost:8888
the way to read the above url is

"Using HTTP, go to the machine called localhost, where on port 8888 someone is waiting"
When the port number is not specified, the default port is 80.

TCP Address Format

net.tcp://localhost:8888/MyService

When a port number is not specified, the default port is 808:

net.tcp://localhost/MyService

NOTE: Two HTTP and TCP addresses from the same host can share a port, even on the same machine.

IPC Address Format
net.pipe://localhost/MyPipe

We can only open a named pipe once per machine, and therefore it is not possible for two named pipe addresses to share a pipe name on the same machine.

MSMQ Address Format
net.msmq://localhost/private/MyService
net.msmq://localhost/MyService

What is Proxy and how to generate proxy for WCF Services?

The proxy is a CLR class that exposes a single CLR interface representing the service contract. The proxy provides the same operations as service's contract, but also has additional methods for managing the proxy life cycle and the connection to the service. The proxy completely encapsulates every aspect of the service: its location, its implementation technology and runtime platform, and the communication transport.

The proxy can be generated using Visual Studio by right clicking Reference and clicking on Add Service Reference. This brings up the Add Service Reference dialog box, where you need to supply the base address of the service (or a base address and a MEX URI) and the namespace to contain the proxy.

Proxy can also be generated by using SvcUtil.exe command-line utility. We need to provide SvcUtil with the HTTP-GET address or the metadata exchange endpoint address and, optionally, with a proxy filename. The default proxy filename is output.cs but you can also use the /out switch to indicate a different name.

SvcUtil http://localhost/MyService/MyService.svc /out:Proxy.cs

When we are hosting in IIS and selecting a port other than port 80 (such as port 88), we must provide that port number as part of the base address:

SvcUtil http://localhost:88/MyService/MyService.svc /out:Proxy.cs

What are different elements of WCF Srevices Client configuration file?

WCF Services client configuration file contains endpoint, address, binding and contract. A sample client config file looks like

<system.serviceModel>

   <client>
      <endpoint name = "MyEndpoint"
         address  = "http://localhost:8000/MyService/"
         binding  = "wsHttpBinding"
         contract = "IMyContract"
      />
   </client>

</system.serviceModel>

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.

How to configure Reliability while communicating with WCF Services?

Reliability can be configured in the client config file by adding reliableSession under binding tag.

<system.serviceModel>
   <services>
      <service name = "MyService">
         <endpoint
            address  = "net.tcp://localhost:8888/MyService"
            binding  = "netTcpBinding"
            bindingConfiguration = "ReliableCommunication" 

            contract = "IMyContract"
         />
      </service>
   </services>
   <bindings>

      <netTcpBinding>

         <binding name = "ReliableCommunication">

            <reliableSession enabled = "true"/> 

         </binding>

      </netTcpBinding>
  </bindings>
</system.serviceModel>

Reliability is supported by following bindings only

NetTcpBinding
WSHttpBinding
WSFederationHttpBinding
WSDualHttpBinding

How to set the timeout property for the WCF Service client call?

The timeout property can be set for the WCF Service client call using binding tag.

<client>
   <endpoint
      ...

      binding = "wsHttpBinding"
      bindingConfiguration = "LongTimeout" 

      ...

   />
</client>
<bindings>
   <wsHttpBinding>
      <binding name = "LongTimeout" sendTimeout = "00:04:00"/>

   </wsHttpBinding>
</bindings>

If no timeout has been specified, the default is considered as 1 minute.

How to deal with operation overloading while exposing the WCF services?

By default overload operations (methods) are not supported in WSDL based operation. However by using Name property of OperationContract attribute, we can deal with operation overloading scenario.

[ServiceContract]
interface ICalculator
{
   [OperationContract(Name = "AddInt")]

   int Add(int arg1,int arg2);

   [OperationContract(Name = "AddDouble")]
   double Add(double arg1,double arg2);
}

.Net realtime Interview Questions ?

1.What are the disadvantages of Javascript?

1.Security. Because the code executes on the users' computer, in some cases it can be exploited for malicious purposes. This is one reason some people choose to disable JavaScript.

2.Reliance on End User. JavaScript is sometimes interpreted differently by different browsers. Whereas server-side scripts will always produce the same output, client-side scripts can be a little unpredictable. Don't be overly concerned by this though - as long as you test your script in all the major browsers you should be safe.

2.Difference between Html and DHtml?

DHTML:
DHTML is the art of combining HTML, JavaScript, DOM, and CSS
DHTML is Not a Language
DHTML stands for Dynamic HTML.
DHTML is NOT a language or a web standard.
DHTML is a TERM used to describe the technologies used to make web pages dynamic and interactive.
To most people DHTML means the combination of HTML, JavaScript, DOM, and CSS.

HTML:
HTML stands for Hyper Text Markup Language,HTML is not a programming language, it is a markup language, A markup language is a set of markup tags
HTML uses markup tags to describe web pages
HTML documents describe web pages, contain HTML tags and plain text
HTML documents are also called web pages

3.Difference between N-tier and 3-tier?

3-tier:

A 3-tier application basically resembles a system with 3 levels or tier, the first is the client tier, second is server tier and the third tier is your data tier.

N-tier:
N-tier application is just an extension of this in which we again split these individual tiers into different tiers and thus the name N-tier.

4.Difference between .net 4.0 and 4.5?

The next major release of the .NET Framework, .NET 4.5, allows you to easily use Windows 8 technologies, like Windows Runtime, directly from .NET 4.5. Accessing your data is easier than ever with support for the newest features in SQL Server and support for WebSockets. Programs are more responsive, with the AWAIT keyword, faster ASP.NET startup and an improved server Garbage Collector. .NET 4.5 incorporates key customer feedback, with the newest MEF features, support for long running workflows with State Machines, and improved HTML 5 support in ASP.NET. In this overview talk, you’ll learn about all of these technologies, and get pointers to deeper dives where you can learn more.

5.What is the use of Ajax?

There are a couple of reasons to use AJAX in lieu of the traditional form submission.

1.Ajax  is very light weight: instead of sending all of the form information to the server and getting all of the rendered HTML back, simply send the data the server needs to process and get back only what the client needs to process. Light weight means fast.

2. The second reason to use AJAX is because (as the logo in the link above makes clear) AJAX is cool.

3. AJAX is a client side technology that uses JavaScript, the client-server interaction is very important.

6.Difference between MVP and MVC?

The two patterns are having much similarities compare to their differences. The both patterns are evolved on separation of concerns and both contain Views and Models.But when comes to the difference part, the major difference is the way handling the incoming request.
In MVP, the incoming request comes to View and View is delegating it to presenter. And presenter is responsible for talk to model and update the view. Here model is completely shielding from View.
 Where as in MVC, all incoming requests are intercepting by the controller and controller is responsible for generating the correct View and Model. Here View is aware of the model

The MVP pattern will built on ASP.Net WebForms. The WebForms development paradigm uses Viewstate. In large Web application it will cause some performance issues.
ASP.Net MVC is new alternative frame work and it view is state less.

7.What is Namespace?

A Namespace in Microsoft .Net is like containers of objects. They may contain unions, classes, structures, interfaces, enumerators and delegates. Main goal of using namespace in .Net is for creating a hierarchical organization of program. In this case a developer does not need to worry about the naming conflicts of classes, functions, variables etc., inside a project.

8.What is the use of SilverLight?

Microsoft Silverlight is an application framework for writing and running rich Internet applications, with features and purposes similar to those of Adobe Flash. The run-time environment for Silverlight is available as a plug-in for web browsers running under Microsoft Windows and Mac OS X. While early versions of Silverlight focused on streaming media, current versions support multimedia, graphics and animation, and give developers support for CLI languages and development tools. Silverlight is also one of the two application development platforms for Windows Phone.

9.Explain about your Project? How much time you taken to complete the project?

10.What is your Role in your project?

Explain the page life cycle in ASP.NET :

ASP.NET  Page Life Cycle - The lifetime of an ASP.NET Page is filled with events. A series of processing steps takes place during this page life cycle. Following tasks are performed:

* Initialization
* Instantiation of controls
* Restoration & Maintainance of State
* Running Event Handlers
* Rendering of data to the browser

The life cycle may be broken down into Stages and Events. The stages reflect the broad spectrum of tasks performed. The following stages take place

Page life cycle Stages:

1) Page request - This is the first stage, before the page life cycle starts. Whenever a page is requested, ASP.NET detects whether the page is to be requested, parsed and compiled or whether the page can be cached from the system.
2) Start - In this stage, properties such as Request and Response are set. Its also determined at this stage whether the request is a new request or old, and thus it sets the IsPostBack property in the Start stage of the page life cycle.
3) Page Initialization - Each control of the page is assigned a unique identification ID. If there are themes, they are applied. Note that during the Page Initialization stage, neither postback data is loaded, nor any viewstate data is retrieved.
4) Load - If current request is a postback, then control values are retrieved from their viewstate.
5) Validation - The validate method of the validation controls is invoked. This sets the IsValid property of the validation control.
6) PostBack Event Handling –Event handlers are invoked, in case the request is a postback.
7) Rendering - Viewstate for the page is saved. Then render method for each control is called. A textwriter writes the output of the rendering stage to the output stream of the page's Response property.
8) Unload - This is the last stage in the page life cycle stages. It is invoked when the page is completely rendered. Page properties like Respone and Request are unloaded.

Note that each stage has its own events within it. These events may be used by developers to handle their code. Listed below are page events that are used more frequently.

Page life cycle Events:

PreInit - Checks the IsPostBack property. To create or recreate dynamic controls. To set master pages dynamically. Gets and Sets profile propety values.
Init - Raised after all controls are initialized, and skin properties are set.
InitComplete - This event may be used, when we need to be sure that all initialization tasks are complete.
PreLoad - If processing on a control or a page is required before the Load event.
Load - invokes the OnLoad event on the page. The same is done for each child control on the page. May set properties of controls, create database connections.
Control Events - These are the control specific events, such as button clicks, listbox item selects etc.
LoadComplete - To execute tasks that require that the complete page has been loaded.
PreRender - Some methods are called before the PreRenderEvent takes place, like EnsureChildControls, data bound controls that have a dataSourceId set also call the DataBind method.
Each control of the page has a PreRender event. Developers may use the prerender event to make final changes to the controls before it is rendered to the page.
SaveStateComplete - ViewState is saved before this event occurs. However, if any changes to the viewstate of a control is made, then this is the event to be used. It cannot be used to make changes to other properties of a control.
Render - This is a stage, not an event. The page object invokes this stage on each control of the page. This actually means that the ASP.NET server control's HTML markup is sent to the browser.
Unload - This event occurs for each control. It takes care of cleanup activities like wiping the database connectivities.

what is the difference between session.abandon() and session.clear() ?

 Session.Abandon():

          Session.Abandon() destroys the session

       Abandon will destroy the session completely, meaning that you need to begin a new session before you can store any more values in the session for that user.

 Session.Clear():

Session.Clear() just removes all values

                Clearing the session will not unset the session, it still exists with the same ID for the user but with the values simply cleared.
The Clear method removes all keys and values from the current session. Compare to Abandon method, it doesn’t create the new session, It just make all variables in session to NULL.

Diff B/w Session.Clear() and Session.RemoveAll():

actually there is no difference. Session.RemoveAll() methods internally makes a call to Clear() method only.

ASP.Net Frequently asked interview questions

ASP.Net Frequently asked interview questions :

How can files be uploaded to Web pages in ASP.NET?

This can be done by using the HtmlInputFile class to declare an instance of an  

<input type="file" runat="server"/> tag. 

Then, a byte[] can be declared to read in the data from the input file. This can then be sent to the server.

How do I create an ASPX page that periodically refreshes itself?

The following META tag can be used as a trigger to automatically refresh the page every n seconds:

<meta http-equiv="Refresh" content="nn">

How do I initialize a TextBox whose TextMode is "password", with a password?

The TextBox’s Text property cannot be used to assign a value to a password field. Instead, its Value field can be used for that purpose.

<asp:TextBox Value="imbatman" TextMode="Password"ID="Password" RunAt="server" />

When was ASP.NET released?

ASP.NET is a part of the .NET framework which was released as a software platform in 2002.

Explain Namespace.

Namespaces are logical groupings of names used within a program. There may be multiple namespaces in a single application code, grouped based on the identifiers’ use. The name of any given identifier must appear only once in its namespace.

What is Authentication in ASP.NET?

Authentication is the process of verifying user’s details and find if the user is a valid user to the system or not. This process of authentication is needed to provide authority to the user. ASP.NET implements authentication through authentication providers. Each provider has OnAuthenticate event. It allows building a custom authorization scheme.

What is Authorization in ASP.NET?

Authorization is a process that takes place based on the authentication of the user. Once authenticated, based on user’s credentials, it is determined what rights des a user have. In ASP.NET, there are two ways to authorize access to a given resource:
a. File authorization
b. URL authorization