IMPORTANT ASP.NET interview questions

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, likeDataGrid,
   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 itsconstituents.
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();")

   A simple”Javascript:ClientCode();” in the button control of the .aspx
   page will attach the handler (javascript function)to the onmouseover event.

9. What data type does the RangeValidator control support? Integer,String
   and Date.
10. Where would you use an iHTTPModule, and what are the limitations of any
    approach you might take in implementing one? One of ASP.NET’s most useful
    features is the extensibility
    of the HTTP pipeline, the path that data takes between client and server.
    You can use them to extend your ASP.NET applications by adding pre- and post-processing
    to each HTTP request coming into your application. For example, if you wanted
    custom authentication facilities for your application, the best technique
    would be to intercept the request when it comes in and process the request
    in a custom HTTP module.
11. Explain what a diffgram is, and a good use for one? A DiffGram is
    an XML format that is used to identify current and original versions of data
    elements. The DataSet uses the DiffGram format to load and persist its contents,
    and to serialize its contents for transport across a network connection. When
    a DataSet is written as a DiffGram, it populates the DiffGram with all the
    necessary information to accurately recreate the contents, though not the
    schema, of the DataSet, including column values from both the Original and
    Current row versions, row error information, and row order.