Describe the role of inetinfo.exe, aspnet_isapi.dll andaspnet_wp.exe in the page
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.
Can you explain the difference between an ADO.NET Dataset and an ADO Recordset?
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 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.
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.
What data types do the RangeValidator control support?
Integer, String, and Date.
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.
What is the transport protocol you use to call a Web service?
SOAP (Simple Object Access Protocol) is the preferred protocol.
What is ViewState?
ViewState allows the state of objects (serializable) to be stored in a hidden
field on the page. ViewState is transported to the client and back to the
server, and is not stored on the server or any other external source. ViewState
is used the retain the state of server-side objects between postabacks.
What does the "EnableViewState" property do? Why would I want it on or off?
It allows the page to save the users input on a form across postbacks. It saves
the server-side values for a given control into ViewState, which is stored as a
hidden value on the page before sending the page to the clients browser. When
the page is posted back to the server the server control is recreated with the
state stored in viewstate.
What are the different types of Session state management options available with
ASP.NET provides In-Process and Out-of-Process state management. In-Process
stores the session in memory on the web server. This requires the a
"sticky-server" (or no load-balancing) so that the user is always reconnected
to the same web server. Out-of-Process Session state management stores data in
an external data source. The external data source may be either a SQL Server or
a State Server service. Out-of-Process state management requires that all
objects stored in session are serializable.
Differences Between XML and HTML?
Anyone with a fundamental grasp of XML should be able describe some of the main
differences outlined in the table below
|User definable tags
||Defined set of tags designed for web display
|End tags required for well formed documents
||End tags not required
|Quotes required around attributes values
||Quotes not required
|Slash required in empty tags
||Slash not required
Give a few examples of types of applications that can benefit from using XML.
There are literally thousands of applications that can benefit from XML
technologies. The point of this question is not to have the candidate rattle
off a laundry list of projects that they have worked on, but, rather, to allow
the candidate to explain the rationale for choosing XML by citing a few real
world examples. For instance, one appropriate answer is that XML allows content
management systems to store documents independently of their format, which
thereby reduces data redundancy. Another answer relates to B2B exchanges or
supply chain management systems. In these instances, XML provides a mechanism
for multiple companies to exchange data according to an agreed upon set of
rules. A third common response involves wireless applications that require WML
to render data on hand held devices.
What is DOM and how does it relate to XML?
The Document Object Model (DOM) is an interface specification maintained by the
W3C DOM Workgroup that defines an application independent mechanism to access,
parse, or update XML data. In simple terms it is a hierarchical model that
allows developers to manipulate XML documents easily Any developer that has
worked extensively with XML should be able to discuss the concept and use of
DOM objects freely. Additionally, it is not unreasonable to expect advanced
candidates to thoroughly understand its internal workings and be able to
explain how DOM differs from an event-based interface like SAX.
What is SOAP and how does it relate to XML?
The Simple Object Access Protocol (SOAP) uses XML to define a protocol for the
exchange of information in distributed computing environments. SOAP consists of
three components: an envelope, a set of encoding rules, and a convention for
representing remote procedure calls. Unless experience with SOAP is a direct
requirement for the open position, knowing the specifics of the protocol, or
how it can be used in conjunction with HTTP, is not as important as identifying
it as a natural application of XML.
Can you walk us through the steps necessary to parse XML documents?
Superficially, this is a fairly basic question. However, the point is not to
determine whether candidates understand the concept of a parser but rather have
them walk through the process of parsing XML documents step-by-step.
Determining whether a non-validating or validating parser is needed, choosing
the appropriate parser, and handling errors are all important aspects to this
process that should be included in the candidate's response.
What are possible implementations of distributed applications in .NET?
.NET Remoting and ASP.NET Web Services. If we talk about the Framework Class
Library, noteworthy classes are in System.Runtime.Remoting and
What are the consideration in deciding to use .NET Remoting or ASP.NET Web
Remoting is a more efficient communication exchange when you can control both
ends of the application involved in the communication process. Web Services
provide an open-protocol-based exchange of informaion. Web Services are best
when you need to communicate with an external organization or another
What’s a proxy of the server object in .NET Remoting?
It’s a fake copy of the server object that resides on the client side and
behaves as if it was the server. It handles the communication between real
server object and the client object. This process is also known as marshaling.
What are remotable objects in .NET Remoting?
Remotable objects are the objects that can be marshaled across the application
domains. You can marshal by value, where a deep copy of the object is created
and then passed to the receiver. You can also marshal by reference, where just
a reference to an existing object is passed.
What are channels in .NET Remoting?
Channels represent the objects that transfer the other serialized objects from
one application domain to another and from one computer to another, as well as
one process to another on the same box. A channel must exist before an object
can be transferred.
What security measures exist for .NET Remoting in System.Runtime.Remoting?
None. Security should be taken care of at the application level. Cryptography
and other security techniques can be applied at application or server level.
What is a formatter?
A formatter is an object that is responsible for encoding and serializing data
into messages on one end, and deserializing and decoding messages into data on
the other end.
Choosing between HTTP and TCP for protocols and Binary and SOAP for formatters,
what are the trade-offs?
Binary over TCP is the most effiecient, SOAP over HTTP is the most
What’s SingleCall activation mode used for?
If the server object is instantiated for responding to just one single request,
the request should be made in SingleCall mode.
What’s Singleton activation mode?
A single object is instantiated regardless of the number of clients accessing
it. Lifetime of this object is determined by lifetime lease.
How do you define the lease of the object?
By implementing ILease interface when writing the class code.
Can you configure a .NET Remoting object via XML file?
Yes, via machine.config and application level .config file (or web.config in
ASP.NET). Application-level XML settings take precedence over machine.config.
How can you automatically generate interface for the remotable object in .NET
with Microsoft tools?
Use the Soapsuds tool.