ASP.NET Interview Questions - 1

1. Describe the role of inetinfo.exe, aspnet_isapi.dll andaspnet_wp.exe in the page loading process.

inetinfo.exe is theMicrosoft IIS server running, handling ASP.NET requests among other things.When an ASP.NET request is received (usually a file with .aspx extension),the ISAPI filter aspnet_isapi.dll takes care of it by passing the request tothe actual worker process aspnet_wp.exe.

2. What’s the difference between Response.Write() andResponse.Output.Write()?

The latter one allows you to write formattedoutput.

3. What methods are fired during the page load?

Init() - when the pageis instantiated, Load() - when the page is loaded into server memory,PreRender() - the brief moment before the page is displayed to the user asHTML, Unload() - when page finishes loading.

4. Where does the Web page belong in the .NET Framework class hierarchy?

System.Web.UI.Page

5. Where do you store the information about the user’s locale?

System.Web.UI.Page.Culture

6. What’s the difference between Codebehind="MyCode.aspx.cs" andSrc="MyCode.aspx.cs"?

CodeBehind is relevant to Visual Studio.NET only.

7. What’s a bubbled event?

When you have a complex control, like DataGrid, writing an event processing routine for each object (cell, button, row, etc.) is quite tedious. The controls can bubble up their eventhandlers, allowing the main DataGrid event handler to take care of its constituents.

8. Suppose you want a certain ASP.NET function executed on MouseOver overa certain button. Where do you add an event handler?

It’s the Attributesproperty, the Add function inside that property. So btnSubmit.Attributes.Add("onMouseOver","someClientCode();")

9. What data type does the RangeValidator control support?

Integer,String and Date.

10. Explain the differences between Server-side and Client-side code?

Server-side code runs on the server. Client-side code runs in the clients’ browser.

11. What type of code (server or client) is found in a Code-Behind class?

Server-side code.

12. Should validation (did the user enter a real date) occur server-side or client-side? Why?

Client-side. This reduces an additional request to the server to validate the users input.

13. What does the "EnableViewState" property do? Why would I want it on or off?

It enables the viewstate on the page. It allows the page to save the users input on a form.

ASP.NET Interview Questions - 2

1. What is the difference between Server.Transfer and Response.Redirect? Why would I choose one over the other?

Server.Transfer is used to post a form to another page. Response.Redirect is used to redirect the user to another page or site.

2. Can you explain the difference between an ADO.NET Dataset and an ADO Recordset?

· A DataSet can represent an entire relational database in memory, complete with tables, relations, and views.
· A DataSet is designed to work without any continuing connection to the original data source.
· Data in a DataSet is bulk-loaded, rather than being loaded on demand.
· There's no concept of cursor types in a DataSet.
· DataSets have no current record pointer You can use For Each loops to move through the data.
· You can store many edits in a DataSet, and write them to the original data source in a single operation.
· Though the DataSet is universal, other objects in ADO.NET come in different versions for different data sources.


3. Can you give an example of what might be best suited to place in the Application_Start and Session_Start subroutines?

This is where you can set the specific variables for the Application and Session objects.


4. If I’m developing an application that must accommodate multiple security levels though secure login and my ASP.NET web application is spanned across three web-servers (using round-robin load balancing) what would be the best approach to maintain login-in state for the users?

Maintain the login state security through a database.


5. Can you explain what inheritance is and an example of when you might use it?

When you want to inherit (use the functionality of) another class. Base Class Employee. A Manager class could be derived from the Employee base class.


6. Whats an assembly?

Assemblies are the building blocks of the .NET framework.


7. Explain what a diffgram is, and a good use for one?

The DiffGram is one of the two XML formats that you can use to render DataSet object contents to XML. For reading database data to an XML file to be sent to a Web Service.


8. Whats MSIL, and why should my developers need an appreciation of it if at all?

MSIL is the Microsoft Intermediate Language. All .NET compatible languages will get converted to MSIL.


9. Which method do you invoke on the DataAdapter control to load your generated dataset with data?

The .Fill() method


10. Can you edit data in the Repeater control?

No, it just reads the information from its data source


11. Which template must you provide, in order to display data in a Repeater control?

ItemTemplate


12. How can you provide an alternating color scheme in a Repeater control?

Use the AlternatingItemTemplate


13. What property must you set, and what method must you call in your code, in order to bind the data from some data source to the Repeater control?

You must set the DataSource property and call the DataBind method.

ASP.NET Interview Questions - 3

1. What base class do all Web Forms inherit from?

The Page class.

2. Name two properties common in every validation control?

ControlToValidate property and Text property.

3. What tags do you need to add within the asp:datagrid tags to bind columns manually?

Set AutoGenerateColumns Property to false on the datagrid tag.

4. What tag do you use to add a hyperlink column to the DataGrid?

5. What is the transport protocol you use to call a Web service?

SOAP is the preferred protocol.

6. True or False: A Web service can only be written in .NET?
False

7. What does WSDL stand for?

(Web Services Description Language)

9. Which property on a Combo Box do you set with a column name, prior to setting the DataSource, to display data in the combo box?

DataTextField property

10. Which control would you use if you needed to make sure the values in two different controls matched?

CompareValidator Control

11. True or False: To test a Web service you must create a windows application or Web application to consume this service?

False, the webservice comes with a test page and it provides HTTP-GET method to test.

12. How many classes can a single .NET DLL contain?
It can contain many classes.

Asp.NET 2.0 Job Interview Questions (Part 1)

1. What are the new Data Controls in Asp.net 2.0?

Data access in ASP.NET 2.0 can be accomplished completely declaratively (no code) using the new data-bound and data source controls. There are new data source controls to represent different data backends such as SQL database, business objects, and XML, and there are new data-bound controls for rendering common UI for data, such as gridview, detailsview, and formview.

2. What are the new Navigation Controls in Asp.net 2.0?

The navigation controls provide common UI for navigating between pages in your site, such as treeview, menu, and sitemappath. These controls use the site navigation service in ASP.NET 2.0 to retrieve the custom structure you have defined for your site.

3. What are the new Login Controlsin Asp.net 2.0?

The new login controls provide the building blocks to add authentication and authorization-based UI to your site, such as login forms, create user forms, password retrieval, and custom UI for logged in users or roles. These controls use the built-in membership and role services in ASP.NET 2.0 to interact with the user and role information defined for your site.

4. What are the new Web Part Controls in Asp.net 2.0 ?

Web parts are an exciting new family of controls that enable you to add rich, personalized content and layout to your site, as well as the ability to edit that content and layout directly from your application pages. These controls rely on the personalization services in ASP.NET 2.0 to provide a unique experience for each user in your application.

5. What are Master Pages?

This feature provides the ability to define common structure and interface elements for your site, such as a page header, footer, or navigation bar, in a common location called a "master page", to be shared by many pages in your site. In one simple place you can control the look, feel, and much of functionality for an entire Web site. This improves the maintainability of your site and avoids unnecessary duplication of code for shared site structure or behavior.

6. What are Themes and Skins in 2.0, explain usgae scenario?

The themes and skins features in ASP.NET 2.0 allow for easy customization of your site's look-and-feel. You can define style information in a common location called a "theme", and apply that style information globally to pages or controls in your site. Like Master Pages, this improves the maintainability of your site and avoid unnecessary duplication of code for shared styles.

7. What is a profile object, why is it used?

Using the new personalization services in ASP.NET 2.0 you can easily create customized experiences within Web applications. The Profile object enables developers to easily build strongly-typed, sticky data stores for user accounts and build highly customized, relationship based experiences. At the same time, a developer can leverage Web Parts and the personalization service to enable Web site visitors to completely control the layout and behavior of the site, with the knowledge that the site is completely customized for them. Personalizaton scenarios are now easier to build than ever before and require significantly less code and effort to implement.

8. What is Configuration API?

ASP.NET 2.0 contains new configuration management APIs, enabling users to programmatically build programs or scripts that create, read, and update Web.config and machine.config configuration files.

9. What is MMC Admin Tool?

ASP.NET 2.0 provides a new comprehensive admin tool that plugs into the existing IIS Administration MMC, enabling an administrator to graphically read or change common settings within our XML configuration files.

10. Explain the use of Pre-compilation Tool?

ASP.NET 2.0 delivers a new application deployment utility that enables both developers and administrators to precompile a dynamic ASP.NET application prior to deployment. This precompilation automatically identifies any compilation issues anywhere within the site, as well as enables ASP.NET applications to be deployed without any source being stored on the server (one can optionally remove the content of .aspx files as part of the compile phase), further protecting your intellectual property.

11. How is application management and maintenance improved in Asp.net 2.0?

ASP.NET 2.0 also provides new health-monitoring support to enable administrators to be automatically notified when an application on a server starts to experience problems. New tracing features will enable administrators to capture run-time and request data from a production server to better diagnose issues. ASP.NET 2.0 is delivering features that will enable developers and administrators to simplify the day-to-day management and maintenance of their Web applications.

12. What are Provider-driven Application Services? explain in detail?
    ASP.NET 2.0 now includes built-in support for membership (user name/password credential storage) and role management services out of the box. The new personalization service enables quick storage/retrieval of user settings and preferences, facilitating rich customization with minimal code. The new site navigation system enables developers to quickly build link structures consistently across a site. As all of these services are provider-driven, they can be easily swapped out and replaced with your own custom implementation. With this extensibility option, you have complete control over the data store and schema that drives these rich application services.
13. Explain Server Control Extensibility with reference to Asp.net 2.0 ?
    ASP.NET 2.0 includes improved support for control extensibility, such as more base classes that encapsulate common behaviors, improved designer support, more APIs for interacting with client-side script, metadata-driven support for new features like themes and accessibility verification, better state management, and more.
14. What are the Data Source Controls?
    Data access in ASP.NET 2.0 is now performed declaratively using data source controls on a page. In this model, support for new data backend storage providers can be easily added by implementing custom data source controls. Additionally, the SqlDataSource control that ships in the box has built-in support for any ADO.NET managed provider that implements the new provider factory model in ADO.NET.
15. What are Compilation Build Providers?
    Dynamic compilation in ASP.NET 2.0 is now handled by extensible compilation build providers, which associate a particular file extension with a handler that knows how to compile that extension dynamically at runtime. For example, .resx files can be dynamically compiled to resources, .wsdl files to web service proxies, and .xsd files to typed DataSet objects. In addition to the built-in support, it is easy to add support for additional extensions by implementing a custom build provider and registering it in Web.config.
16. What is Expression Builders, why would you use it?
    ASP.NET 2.0 introduces a declarative new syntax for referencing code to substitute values into the page, called Expression Builders. ASP.NET 2.0 includes expression builders for referencing string resources for localization, connection strings, application settings, and profile values. You can also write your own expression builders to create your own custom syntax to substitute values in a page rendering.
17. Is ASP.NET 64-Bit enabled? how?
    ASP.NET 2.0 is now 64-bit enabled, meaning it can take advantage of the full memory address space of new 64-bit processors and servers. Developers can simply copy existing 32-bit ASP.NET applications onto a 64-bit ASP.NET 2.0 server and have them automatically be JIT compiled and executed as native 64-bit applications (no source code changes or manual re-compile are required).
18. Explain how Caching in Asp.net 2.0 is different from Caching in Asp.net 1.1?
    ASP.NET 2.0 also now includes automatic database server cache invalidation. This powerful and easy-to-use feature allows developers to aggressively output cache database-driven page and partial page content within a site and have ASP.NET automatically invalidate these cache entries and refresh the content whenever the back-end database changes. Developers can now safely cache time-critical content for long periods without worrying about serving visitors stale data.