Friday, November 14, 2008 interview questions

Interview Questions

is a list of questions I have gathered and created over a period of
time from my experience, many of which I felt where incomplete
or simply wrong.  I have finally taken the time to go through
each question and correct them to the best of my ability. 
However, please feel free to post feedback to challenge, improve, or
suggest new questions.  I want to thank those of you that have
contributed quality questions and corrections thus far.

are some questions in this list that I do not consider to be good
questions for an interview.  However, they do exist on other
lists available on the Internet so I felt compelled to keep them here
for easy access.

  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()
    Response.Output.Write() allows
    you to write formatted output. 

  3. What
    methods are fired during the page load?
    Init() - when the
    page is instantiated
    Load() - when the page is loaded into server
    PreRender() - the brief moment before the page is
    displayed to the user as HTML
    Unload() - when page finishes

  4. When
    during the page processing cycle is ViewState available?

    the Init() and before the Page_Load(), or OnLoad() for a control. 

  5. What
    namespace does the Web page belong in the .NET Framework class

  6. Where
    do you store the information about the user’s

  7. What’s
    the difference between Codebehind="MyCode.aspx.cs"
    CodeBehind is relevant to
    Visual Studio.NET only. 

  8. 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. 

  9. Suppose
    you want a certain ASP.NET function executed on MouseOver for
    a certain button.  Where do you add an event handler?
    an OnMouseOver attribute to the button.  Example:

  10. What
    data types do the RangeValidator control support?
    String, and Date. 

  11. Explain
    the differences between Server-side and Client-side
    Server-side code executes on the server. 
    Client-side code executes in the client's browser. 

  12. What
    type of code (server or client) is found in a Code-Behind class?
    answer is server-side code since code-behind is executed on the
    server.  However, during the code-behind's execution on the
    server, it can render client-side code such as JavaScript
    to be processed in the clients browser.  But just to
    be clear, code-behind executes on the server, thus making it
    server-side code. 

  13. Should
    user input data validation occur server-side or client-side?
    All user input data validation should occur on the
    server at a minimum.  Additionally, client-side validation can
    be performed where deemed appropriate and feasable to provide a
    richer, more responsive experience for the user. 

  14. What
    is the difference between Server.Transfer and Response.Redirect?
     Why would I choose one over the other?
    transfers page processing from one page directly to the
    next page without making a round-trip back to the client's browser. 
    This provides a faster response with a little less overhead on the
    server.  Server.Transfer does not update the clients url
    history list or current url.  Response.Redirect is used to
    redirect the user's browser to another page or site.  This
    performas a trip back to the client where the client's browser is
    redirected to the new page.  The user's browser history list is
    updated to reflect the new address. 

  15. Can
    you explain the difference between an ADO.NET Dataset and an ADO
    Valid answers are:
    ·  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
    ·  Though the DataSet is universal, other
    objects in ADO.NET come in different versions for different data

  16. What
    is the Global.asax used for?

    Global.asax (including the Global.asax.cs file) is used to implement
    application and session level events. 

  17. What are
    the Application_Start and Session_Start subroutines used for?
    is where you can set the specific variables for the Application and
    Session objects. 

  18. Can
    you explain what inheritance is and an example of when you might use
    When you want to inherit (use the functionality of)
    another class.  Example: With a base class named Employee,
    a Manager class could be derived from the Employee base class. 

  19. Whats
    an assembly?
    Assemblies are the building blocks of the .NET

    Overview of assemblies from MSDN

  20. Describe
    the difference between inline and code behind.
    Inline code
    written along side the html in a page. Code-behind is code written
    in a separate file and referenced by the .aspx page. 

  21. 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.  A good use is reading database data to
    an XML file to be sent to a Web Service. 

  22. Whats
    MSIL, and why should my developers need an appreciation of it if at
    MSIL is the Microsoft Intermediate Language. All .NET
    compatible languages will get converted to MSIL.  MSIL also
    allows the .NET Framework to JIT compile the assembly on the
    installed computer. 

  23. Which
    method do you invoke on the DataAdapter control to load your
    generated dataset with data?
    The Fill() method. 

  24. Can
    you edit data in the Repeater control?
    No, it just reads the
    information from its data source

  25. Which
    template must you provide, in order to display data in a Repeater

  26. How
    can you provide an alternating color scheme in a Repeater
    Use the AlternatingItemTemplate

  27. What
    property must you set, and what method must you call in your code,
    in order to bind the data from a data source to the Repeater
    You must set the DataSource property and call the
    DataBind method. 

  28. What
    base class do all Web Forms inherit from?
    The Page class. 

  29. Name
    two properties common in every validation control?
    property and Text property. 

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

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

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