VB.NET Interview Question And Answers

1)Distinguish between VB and VB.net
VB
1.Object-based Language
2.Does not support Threading,inheritance
3.Not powerful Exception handling mechanism
4.Does not support console based applications
5.Cannot use more than one version of COM objects in vb application
called DLL error.
6.Does not support Disconnected data source.

VB.Net
1.Object-oriented Language
2.supports Threading
3.powerful Exception handling mechanism
4.Supports console based applications
5.More than one version of DLL is supported.
6.supports Disconnected data source using data source class

2. Compare C# and VB.NET?
C#
1. C# has concepts from many languages such as Delphi, Java, etc and syntax from C and Java.
2. C# is a console
3. C# uses Must not Inherit
4. C# uses Internal
5. C# uses abstract

VB.Net
1.Visual basic has been updated and revised to make it object oriented
2.VB.NET is a windows application
3.VB.Net uses sealed class
4.VB.Net uses friend
5. VB.Net uses Must Inherit

3.Whats the main difference between .dll extension and .exe extension?
.dll extension files: It is the In process component.
It uses client's memory to run.
communication between the application and component (.dll) is very fast.

.EXE extension files:
It is the Out of process component.
It uses its own memory not application memory to run the component.
communication between the application and component is slow compared to .dll

6. Define delegate.
These are object oriented function pointers. allows us to handle callbacks and events. can invoke the methods that refer to those methods without making explicit calls It encapsulates the memory address of function in our code.
Whenever we create or use an event in code, we are using a delegate. When the event is thrown, the framework examines the delegate behind the event and then calls the function which the delegate points to. This can be combined to form groups of functions that can be called together.
We use delegates to let procedures specify an event handler method that runs when an event occurs.
We also use delegates with multithreaded applications.

7.Difference between CLR & CTS?
CLR : is the common language runtime.
It makes the .net application to run plantform independent langauge interoperability.
It is the heart of the .net framework.
every runtime has responsibility to take care of code at the time of execution.
Example vb has MSCRT60 , java has JVM and .net has CLR.


CTS : Common type system is the subset of the CLR.
It enables the Common Datatype system to All the .net languages.
It defines conventions to convert objects from one langauge to another
It provides smooth comunication between two language.
Example vb .net has integer and c# has int , CTS change both into system.int32

8.What is the difference between manifest and metadata?
There are 2 parts of assembly architecture. They are
1. Manifest
2. Metadata

1. Manifest :

used for storing AssemblyName, AssemblyTitle, publicKey.
assembly manifest contains this assembly metadata.
can be stored in either a PE file (an .exe or .dll) with Microsoft intermediate language (MSIL) code or in a standalone PE file that contains only assembly
manifest information.

2. Metadata :

Metadata contains Namespaces, Classes.
Metadata is binary information describing our program which is stored either in a common language runtime portable executable (PE) file or in memory.
When we compile our code into a PE file, metadata is inserted into one portion of the file, while your code is converted to Microsoft intermediate language (MSIL) and inserted into another portion of the file.
Every type and member defined and referenced in a module or assembly is described within metadata.
When code is executed, the runtime loads metadata into memory and references it to discover information about your code's classes, members, inheritance, and so on.

9. What do you mean by Jagged Array in VB.NET and how it differs from multidimensional array?
Jagged Array :
Jagged array is multidimensional array.It also contains a table where each row can have a different number of columns.To create a jagged array, we declare the array of arrays with multiple sets of parentheses or brackets and indicate the size of the jagged array in the first set of brackets.

array of array is jagged array and multidimention array can have more than one dimension. multidimentional array has same size in all dimentions but jagged is the type of multidimentional array which has different size for its dimensions.

int array[2][2][2]; - > multidimentional array
int array[2][1][2]; - > jagged array

10.Advantage of VB.NET?
A. References
B. Shared Members
C. Delegates
D. Constructors and Destructors
E. All

Answer: E

11. Which is true regarding VB.NET?
A. does not have XML Documentation.
B. does not have operator overloading
C. does not have pointers
D. All of the above

Answer: D

12. Select the true statement about Recordset and Datset in VB.NET from the following options?
A. RecordSets are fully connected approach
B. Datasets are disconnected approach
C. Both A & B
D. None of the above

Answer: C