.NET And Asp.Net Interview Questions Answers _ 3

[kaja mydeen]

.NET And Asp.Net Interview Questions Answers

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

Answer1:
SOAP. Transport Protocols: It is essential for the acceptance of Web Services that they are based on established Internet infrastructure. This in fact imposes the usage of of the HTTP, SMTP and FTP protocols based on the TCP/IP family of transports. Messaging Protocol: The format of messages exchanged between Web Services clients and Web Services should be vendor neutral and should not carry details about the technology used to implement the service. Also, the message format should allow for extensions and different bindings to specific transport protocols. SOAP and ebXML Transport are specifications which fulfill these requirements. We expect that the W3C XML Protocol Working Group defines a successor standard.

Answer2:
SOAP is not the transport protocol. SOAP is the data encapsulation protocol that is used but the transport protocol is fairly unlimited. Generally HTTP is the most common transport protocol used though you could conceivanly use things like SMTP or any others. SOAP is not dependant on any single transport protocol or OS, it is a syntactical and logical definition, not a transport protocol.

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

False.

What does WSDL stand for?

Web Services Description Language

Where on the Internet would you look for Web services?

UDDI repositaries like uddi.microsoft.com, IBM UDDI node, UDDI Registries in Google Directory, enthusiast sites like XMethods.net.

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

Column tag and an ASP:databound tag.

How is a property designated as read-only?

In VB.NET:
Public ReadOnly Property PropertyName As ReturnType
Get 'Your Property Implementation goes in here
End Get
End Property

in C#
public returntype PropertyName
{
get{
//property implementation goes here
}
// Do not write the set implementation
}

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

Use the CompareValidator control to compare the values of 2 different controls.

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

How many classes can a single .NET DLL contain?

Unlimited.

Describe session handling in a webfarm, how does it work and what are the limits?

Set the sessionState mode in the web.config file to "StateServer".
StateServer mode uses an out-of-process Windows NT Server to store state information.
It solves the session state loss problem in InProc mode.
Allows a webfarm to store session on a central server.
It provides a Single point of failure at the State Server.

Follow these simple steps:

- In a web farm, make sure you have the same in all your web servers.
- Also, make sure your objects are serializable.
- For session state to be maintained across different web servers in the web farm, the Application Path of the website in the IIS Metabase should be identical in all the web servers in the web farm.

What are the disadvantages of viewstate/what are the benefits?

Answer1:
Disadvantage of viewstate is that additional data is sent to the browser. The benefits are that you do not have to manually manage refreshing the page fields after a submit, (when re-displaying the same page).

Answer2:
Automatic view-state management is a feature of server controls that enables them to repopulate their property values on a round trip (without you having to write any code). This feature does impact performance, however, since a server control's view state is passed to and from the server in a hidden form field. You should be aware of when view state helps you and when it hinders your page's performance.

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

Answer1:
Set AutoGenerateColumns Property to false on the datagrid tag

Answer2:
tag and either or tags (with appropriate attributes of course)

What is State Management in .Net and how many ways are there to maintain a state in .Net? What is view state?

Web pages are recreated each time the page is posted to the server. In traditional Web programming, this would ordinarily mean that all information associated with the page and the controls on the page would be lost with each round trip.
To overcome this inherent limitation of traditional Web programming, the ASP.NET page framework includes various options to help you preserve changes — that is, for managing state. The page framework includes a facility called view state that automatically preserves property values of the page and all the controls on it between round trips.
However, you will probably also have application-specific values that you want to preserve. To do so, you can use one of the state management options.
Client-Based State Management Options:
View State
Hidden Form Fields
Cookies
Query Strings
Server-Based State Management Options
Application State
Session State
Database Support

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

Depends on who's definition of hyperlink your using. Manually a std html anchor tag (a) will work or you can use the micro-magical tag

What is the standard you use to wrap up a call to a Web service?

Several possible answers depending on your interpretation of the quesiton, but I think you were aiming for SOAP (with the caveat that this is MS's version of SOAP)

What is the difference between boxing and unboxing ?

Boxing allows us to convert value types to reference types. Basically, the runtime creates a temporary reference-type box for the object on heap.
Eg:
int i=20;
object o=i;

Describe the difference between a Thread and a Process?

Answer1:
Thread - is used to execute more than one program at a time.
process - executes single program

Answer2:
A thread is a path of execution that run on CPU, a proccess is a collection of threads that share the same virtual memory. A process have at least one thread of execution, and a thread always run in a process context.

Answer3:
The operating system creates a process for the purpose of running a program. Each process executes a single program. Processes own resources allocated by the operating system. Resources include memory, file handles, sockets, device handles, and windows. Processes do not share address spaces or file resources except through explicit methods such as inheriting file handles or shared memory segments, or mapping the same file in a shared way.
Threads allow a program to do multiple things concurrently. At least one thread exists within each process. If multiple threads can exist within a process, then they share the same memory and file resources.

Answer4:
Thread is a light weight process, which is initialized itself by a process. Light weigt processes does not loads resources required by it itself, these are loaded by its parent process which has generated it.

What is a Windows Service and how does its lifecycle differ from a "standard" EXE?

Windows Service applications are long-running applications that are ideal for use in server environments. The applications do not have a user interface or produce any visual output; it is instead used by other programs or the system to perform operations. Any user messages are typically written to the Windows Event Log. Services can be automatically started when the computer is booted. This makes services ideal for use on a server or whenever you need long-running functionality that does not interfere with other users who are working on the same computer. They do not require a logged in user in order to execute and can run under the context of any user including the system. Windows Services are controlled through the Service Control Manager where they can be stopped, paused, and started as needed.