1. What
is UDDI?
UDDI stands for Universal Description,
Discovery, and Integration. It is like an "Yellow Pages" for Web
Services. It is maintained by Microsoft, IBM, and Ariba, and is designed to
provide detailed information regarding registered Web Services for all vendors.
The UDDI can be queried for specific Web Services.
2. Is
it possible to generate the source code for an ASP.NET Web service from a WSDL?
The Wsdl.exe tool (.NET Framework SDK)
can be used to generate source code for an ASP.NET web service with its WSDL
link.
Example: wsdl /server
http://api.google.com/GoogleSearch.wsdl.
3. Why
do upload fail while using an ASP.NET file upload control to upload large
files?
ASP.NET limits the size of file uploads
for security purposes. The default size is 4 MB. This can be changed by
modifying the maxRequestLength attribute of Machine.config's
<httpRuntime> element.
4. Describe
the difference between inline and code behind.
Inline code is written alongside the HTML
in a page. Code-behind is code written in a separate file and referenced by the
.aspx page.
5. Describe
the role of inetinfo.exe, aspnet_isapi.dll andaspnet_wp.exe in the page loading
process.
inetinfo.exe is the Microsoft 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 to the actual worker
process aspnet_wp.exe.
6. 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.
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. 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.
9. What
is the transport protocol you use to call a Web service?
SOAP (Simple Object Access Protocol) is
the preferred protocol.
10. 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.
11. 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 client’s browser. When the page is posted back to the
server the server control is recreated with the state stored in viewstate.
12. What
are the different types of Session state management options available with
ASP.NET?
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 "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.
13. 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
XML HTML User definable tags Defined set of tags designed for web display
Content driven Format driven 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.
14. 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.
15. 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.
16. 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.
17. 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.
18. 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 System.Web.Services.
19. What
is the consideration in deciding to use .NET Remoting or ASP.NET Web Services?
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 information. Web Services are best when you
need to communicate with an external organization or another (non-.NET)
technology.
20. 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 marshalling.
21. 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.
22. 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.
23. 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.
24. 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.
25. Choosing
between HTTP and TCP for protocols and Binary and SOAP for formatters, what are
the trade-offs?
Binary over TCP is the most efficient; SOAP
over HTTP is the most interoperable.
26. 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.
27. 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.
28. How
do you define the lease of the object?
By implementing ILease interface when
writing the class code.
29. 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.
30. How
can you automatically generate interface for the remotable object in .NET with
Microsoft tools?
Use the Soapsuds tool.
31. How
many classes can a single .NET DLL contain?
It can contain many classes.
0 comments
Post a Comment