1.
What is Cross-Page Posting?
Ø Whenever
you send a request to the server it sends request to the same page.
Ø In
Cross page posting it will send request to another page.
Ø We
can achieve his through postback url
property
2.
What are Web services?
Ø Web services are functions exposed by
server-side applications.
Ø They are programmable units that other
applications (and Web services) can access over the Internet.
Ø Web services are hosted in some
website.
Ø Web services holds business logic which
can be used by any application.
There are three different techniques of
managing session in ASP.NET
Ø 1.InProc : Session state is stored locally in memory of ASP.NET worker
process.
Ø
2.
StateServer : Session state is stored outside
ASP.NET worker process and is managed by Windows service. Location of this
service is specified by stateConnectionString attribute.
Ø
3.SQLServer : Session state is stored outside ASP.NET worker process in
SQL Server database. Location of this database is represented by
sqlConnectionString attribute.
4. What is boxing and unboxing?
Ø Converting a value type to reference type is called Boxing.
Ø Converting reference type of value type
is Unboxing.
int i = 1;
object o = i; // boxing
int j = (int) o; // unboxing
5. What is Property?
Ø A property is a member that provides a flexible mechanism to
read, write, or compute the value of a private field. Properties can be used as
if they are public data members, but they are actually special methods called accessors. This enables data to be accessed easily and still helps
promote the safety and flexibility of methods.
Ø This is an execution engine for .NET
Framework application.
Ø CLR is responsible for take care of
entire execution process.
Ø It will convert MSIL code into Native
Code.
Ø CLR provides the following services
1. Code
Management
2. Application memory isolation
3. Verification of type safety
4. Conversion of IL to native code.
5. Access to meta data
6. Managing memory for managed objects
7. Enforcement of code access security
8. Exception handling, including cross-language exceptions.
9. Inter operation between managed code, COM objects and pre-existing DLLs
(Unmanaged code and data)
10. Automation of object layout
11. Support for developer services (profiling, debugging etc.)
7.
When to use String and StringBuilder class?
Ø Use the String class to
concat, join or format methods to join multiple items in a single statement.
Ø Use StringBuilder class to create dynamic strings.
8.
String is a value type or reference type?
Ø String is a reference type variable.
9. List
few ValueType variables.
System.SByte,
System.Byte
System.Int16
System.Int32
System.Int64
System.Single
System.Double
System.Decimal
System.Char
System.Boolean
System.DateTime
Ø All reference type variables are stored
in heap memory (Random).
Ø All value types variables are stored in
stack memory (Sequential).
11. What is
Singleton pattern?
Ø Singleton pattern ensures a class has
only one instance & provide a global point of access to it.
Ø It is achieved by declaring a static
variable for the class & checking for null before actually instantiating
it.
12. What does
aspx stand for?
Ø Active Server Pages Extension
13. What is CTS?
Ø CTS (Common Type System) is a rich type
system, build into the common language runtime that supports the types and
operations found in most of the programming languages.
Ø The common type system supports the
complete implementation of a wide range of programming language.
14. What is CLS?
Ø CLS (Common Language Specification) is
a set of constructs that serves as a guide for library writers and compiler
writers.It allows libraries to be fully usable from any language supporting the
CLS, and for those languages to integrate with each other.
Ø The CLS is a subset of common type
system. The common language specifications is also important to application
developers wh are writing code that will be used by other developers.
15. What is MSIL?
Ø MSIL (Microsoft Intermediate Language)
is a CPU-Independent instructions set into which .NET Framework programs are
compiled.
Ø It contains instructions for loading,
storing, initializing and calling methods on objects.
Ø System.Threading.Thread.Abort
Ø It is a often used to deploy language
specific resources for an application.
Ø These assemblies work in side-by-side
execution because the application has a separate product ID for each language
& installed satellite assemblies in a language specific sub-directory.
Ø When uninstalling, the application
removes only the satellite assemblies associated within a give language &
.NET Framework version.
18. What is
application domain?
Ø The primary purpose of application
domain is to isolate an application from other application. Win32 process
provides isolation but in distinct memory address spaces. This is effective but
it is expensive and doesn't scale well. The .NET runtime enforces app domain
isolation by keeping control over the use of memory.
Ø All memory in the app domain is managed
by the .net runtime so the runtime can ensure that app domain do not access
each other's memory. Objects in different application domains communicate
either by transporting copies of objects across application domain boundries or
by using a proxy to exchange messages.
19. What is
Remoting in .NET?
Ø
.NET
Remoting offers much more complex functionality including support for passing
objects by values or by references, callbacks & multiple objects activation
^ life cycle management policy.
Ø In order to use Remoting a client need
to build using .NET.
Response.Expires :
This property specifies the number of minutes before a page cached in the
browser expires ie. if the user returns to the same page before the specified
number of minutes the cached version of the page is displayed.
<% Response.Expires = minutes %>
Response.ExpiresAbsolute
Using this property we can set the date and/or time at which page cached in the
browser expires.
<% Response.ExpiresAbsolute=#May 15, 1999 18:00:00# %>
20. What is
typed dataset ?
Ø A typed dataset is very much similar to
a normal dataset. But the only difference is that the sehema is already present
for the same. Hence any mismatch in the column will generate compile time
errors rather than runtime error as in the case of normal dataset.
Ø Also accessing the column value is much
easier than the normal dataset as the column definition will be available in
the schema.
Ø Yes,
provided both have different versions.
Ø GAC
is a Folder that contains .dll that have strong name.
Ø So
we can keep myproject.dll and myproject.dll two files into GAC with different version like 1.0.0.0 and 1.0.0.1
Ø Private
Assembly is used inside an application
only and does not have to be identified by a strong name.
Ø Shared
Assembly can
be used by multiple applications and has to have a strong name.
Ø C:\$WINDOWS\assembly
Ø Just-in-time
compiler is a compiler used to convert the Common Intermediate Language (CIL)
code into native code (also called machine code) that is processed by
machine.
Ø A
little description : While compiling of .NET
program, its code is converted into Common Intermediate Language code that is
done by Common Language Runtime.
But while executing the program this CIL code is converted into Machine code or
Native code that is done by JIT Compiler.
Ø Abstract
class cannot be instantiated instead it has to be inherited.
Ø The
methods in abstract class can be overriden in the child class
Ø Abstract
class can holds both abstract methods and concrete methods.
Ø Abstract
class is desined to act as base class.
Ø Concrete
methods are common to all classes but abstract classes have new implementation
in derived classes.
Ø Managed
Code is
what Visual Basic .NET and C# compilers create. It compiles to Intermediate
Language (IL), not to machine code that could run directly on your computer.
The IL is kept in a file called an assembly, along with metadata that describes
the classes, methods, and attributes (such as security requirements) of the
code you've created. This assembly is the one-stop-shopping unit of deployment
in the .NET world. You copy it to another server to deploy the assembly there—and
often that copying is the only step required in the deployment.
Ø Unmanaged
code is
what you use to make before Visual Studio .NET 2002 was released. Visual Basic
6, Visual C++ 6, heck, even that 15-year old C compiler you may still have
kicking around on your hard drive all produced unmanaged code. It compiled
directly to machine code that ran on the machine where you compiled it—and on
other machines as long as they had the same chip, or nearly the same. It didn't
get services such as security or memory management from an invisible runtime;
it got them from the operating system. And importantly, it got them from the
operating system explicitly, by asking for them, usually by calling an API
provided in the Windows SDK. More recent unmanaged applications got operating
system services through COM calls.
Ø Namespace:
1. It is a Collection of names wherein each name is Unique.
2. They form the logical boundary for a Group of classes.
3. Namespace must be specified in Project-Properties.
Ø Assembly:
1. It is an Output Unit. It is a unit of Deployment & a unit of versioning.
Assemblies contain MSIL code.
2. Assemblies are Self-Describing. [e.g. metadata, manifest]
3. An assembly is the primary building block of a .NET Framework application.
It is a collection of functionality that is built, versioned, and deployed as a
single implementation unit (as one or more files). All managed types and
resources are marked either as accessible only within their implementation
unit, or by code outside that unit.
Ø The
manifest describes the assembly, providing the logical attributes shared by all
the modules and all components in the assembly.
Ø The
manifest contains the assembly name, version number, locale and an optional
strong name that uniquely identifying the assembly.
Ø Metadata
is the complete way of describing what is in a .NET assembly.
Ø Digging
into the metadata yields the types available in that assembly, viz. classes,
interfaces, enums, structs, etc., and their containing namespaces, the name of
each type, its visibility/scope, its base class, the interfaces it implemented,
its methods and their scope, and each method’s parameters, type’s properties,
and so on.
Code
Access Security (CAS), in the Microsoft .NET framework, is Microsoft's solution
to prevent untrusted code from performing privileged actions.
It performs following function
1. Defines permissions and permission sets that represent the right to access
various system resources.
2. Enables administrators to configure security policy by associating sets of
permissions with groups of code (code groups).
3. Enables code to request the permissions it requires in order to run, as well
as the permissions that would be useful to have, and specifies which
permissions the code must never have.
4. Grants permissions to each assembly that is loaded, based on the permissions
requested by the code and on the operations permitted by security policy.
5. Enables code to demand that its callers have specific permissions.
6. Enables code to demand that its callers possess a digital signature, thus
allowing only callers from a particular organization or site to call the
protected code.
7. Enforces restrictions on code at run time by comparing the granted
permissions of every caller on the call stack to the permissions that callers
must have.
Ø The
difference between ApplicationException and SystemException is that
SystemExceptions are thrown by the CLR, and ApplicationExceptions are thrown by
Applications.
Ø Function
Overload is
the another version of the same function into the class. There can be different
parameters, return type in overload functions (in brief: Same function and
different parameters).
Ø Function
Override is
entirely overriding the base class function and creating our own version in the
child class. Base class and child class function name and return type should be
same.
Ø It
is basically trying to do more than one thing at a time within a process.
Ø There
are two main ways of multi-threading which .NET encourages: starting your own
threads with ThreadStart delegates, and using the ThreadPool class either
directly (using ThreadPool.QueueUserWorkItem) or indirectly using asynchronous
methods (such as Stream.BeginRead, or calling
BeginInvoke on any delegate).
Ø An
application can have multiple web.config
files but in different directories .
Ø Mean
each and every directory can have a web.config file.
Ø Database
connection string can be stored in the web config file.
Ø The
.NET Framework provides specialized classes for data storage and retrieval.
Ø Inheritance
Ø Abstraction
Ø Polymorphism
Ø Encapsulation
Ø If
interface inheritance all the methods in
the interface needs to be implemented.
Ø Class
inheritance no need such thing.
Ø Web.config
is an xml configuration file.
Ø It
is never directly called unless we need to retrieve a configurations setting.
Ø Server
name, user id, password, database name.
Ø The
runtime host is the environment in which the CLR is started and managed.
Ø The
application level variable hold value at the application level and their
instances are destroyed when the no more client access that application
Ø whereas
session correspond to a individual user accessing the application.
Ø Virtual
directory is the physical location of the application on the machine.
Ø By
default it’s - inetpub/wwwroot
Ø No,
maintaining value in cookie won’t be possible. In that case you have to make
use of other ways to maintain state of the data on page.
Ø you
can check whether client support cookies or not by using Request.Browser.Cookies property.
Process -
Instance of the application.
Ø Session
- Instance of the user accessing the application.
Ø Cookie - Used for storing
small amount of data on client machine.
Serialization is a process of converting
an object into a stream of bytes.
Ø .Net
has 2 serializers namely XMLSerializer and SOAP/BINARY Serializer.
Ø Serialization
is mainly used in the concept of .Net Remoting.
Ø Overriding - Method has the same signature as the
parent class method.
Ø Overloading
- Method having diff parameters list
or type or the return type may be different.
