.Net Interview Question Part 5

1. Explain dotnet framework ?

The dot net Framework has two main components CLR and .NET Libraries. CLR (common language runtimes), that actually runs the code manages so many things for example code execution, garbage collection, memory allocation, thread management etc. Apart from CLR, the .NET framework contains .NET libraries, which are collection of namespaces and classes. The classes and namespaces are kept in a systematic way and can be used in making any application, code reuability etc. The root namespace of .NET framework is System, with this namespace many namespaces like web (system.web), data

(system.data), windows (system.windows) are generated which can be further have their namespaces.

2. What is the difference between Metadata and Menifest ?

Menifest descriubes the assembely itself. Assembely name, version number, culture information. strong name, list of all files, type reference and reference assembely. While the Metadata describes the contents within the assembely. like classes, interfaces, namespaces, base class, scope, properties and their parameters etc.

3. What are public and private assemblies ? differences and scope ? Public assembly are the dll/exe file that can be used in different application. The main advantage of public assemblies is code reusability. These can be used in different machine on different computers. These are also called as shared assemblies. Private assembly is the assembelyinfo.cs or assembelyinfo.vb file within an application. An application must have one private assembely, outside this application there is no scope of privaet assembely.

5. What is an Assembly ?

Assemblies are the fundamental buildung block of .NET framework. They contains the type and resources that are useful to make an application. Assembly enables code reuse, version control, security and deployment. An assembely can have four parts : Menifest, Type metadata, MSIL and Resource file

5. What is GAC ?

GAC (global assembelu cache) Its an space (directory C:\winnt\assembely) on the server where all the shared assemblies are registrered and that can be used in the application for code reuse.

6. What do you know about Machine.Config file ?

Its a base configuration file for all .NET assemblies running on the

server. It specifies a settings that are global to a perticular machine.

7. Different types of authentication modes in .NET Framework ? Windows, Forms, Passport and None.

8. What is Strong name ?

Strong name ensures the uniqueness of assembely on the server. A strong name incudes information about Assembely version, Public/Private Key token, Culture information and ASsembely name.

9. Where does the GAC exist ?

By defauit C:\\assembely e.g c:\winnt\assembely or c:\windows\assembely

10. What are different types that a variable can be defined and their scopes ?

Public- Can be accessed anywhere

Private- anywhere in the same class

Protected -winthin the class and the class that inherites this class

Friend- Members of the class within the assembely

Protected friend- member of assembely or inheriting class

11. What is DLL HELL ?

Previously (when using VB) we can have a situation that we have to put same name dll file in a single directory , but the dlls are of different versions. This is known as dll hell.

12. What is COM, COM+ and DCOM ?

COM (Component Object Model) A standard that is used to for communication between OS and the softwares. COM is used to create reusable software components

COM+ : COM+ is an extension of Component Object Model (COM). COM+ is both an OOP architecture and a set of operating system services.

DCOM an extension of the Component Object Model (COM) that allows COM components to communicate across network boundaries. Traditional COM components can only perform interprocess communication across process boundaries on the same machine. DCOM uses the RPC mechanism to transparently send and receive information between COM components (i.e., clients and servers) on the same network.

13. What is boxing and unboxing ?

Implicit (manual) conversion of value type to reference type of a variable is known as BOXING, for example integer to object type conversion. Conversion of Boxed type variable back to value type is called as UnBoxing.

14. what is connected and diconnected database ?

Connected and Disconneted database basicallythe approch that how you handle the database connection, It may be connected that once the

application starts you have to open the connection only for a single time and then performs many transactions and close the connection just before exit the application. This approch will be generally used in windows based application. On other hand disconnected architecter refere to open and close the connection for each time while performing a transactio.

15. What is garbage collection and how it works ?

Garbage Collection is Automatic Memory Manager for the dotnet framework. It manages the memory allocated to the .NET framework. CLR takes cares about .NET framework. When a variable is defined, Its gets a space in the memory and when the program control comes out of that function the scope of variable gets ended, so the garbage collection acts on and memory will releases.