C# Interview Questions & Answers

If you are preparing for job interview then this blog will definitely help you

1. Does C# support multiple-inheritance?
No.

2. Who is a protected class-level variable available to?
It is available to any sub-class (a class inheriting this class).

3. Are private class-level variables inherited?
Yes, but they are not accessible. Although they are not visible or accessible via the class interface, they are inherited.

4. Describe the accessibility modifier “protected internal”.
It is available to classes that are within the same assembly and derived from the specified base class.

5. What’s the top .NET class that everything is derived from?
System.Object.

6. What does the term immutable mean?
The data value may not be changed. Note: The variable value may be changed, but the original immutable data value was discarded and a new data value was created in memory.

7. What’s the difference between System.String and System.Text.StringBuilder classes?
System.String is immutable. System.StringBuilder was designed with the purpose of having a mutable string where a variety of operations can be performed.

8. What’s the advantage of using System.Text.StringBuilder over System.String?
StringBuilder is more efficient in cases where there is a large amount of string manipulation. Strings are immutable, so each time a string is changed, a new instance in memory is created.

9. Can you store multiple data types in System.Array?
No.

10. What’s the difference between the System.Array.CopyTo() and System.Array.Clone() ?
The Clone() method returns a new array (a shallow copy) object containing all the elements in the original array. The CopyTo() method copies the elements into another existing array. Both perform a shallow copy. A shallow copy means the contents (each array element) contains references to the same object as the elements in the original array. A deep copy (which neither of these methods performs) would create a new instance of each element’s object, resulting in a different, yet identacle object.

11. How can you sort the elements of the array in descending order?
By calling Sort() and then Reverse() methods.

12. What’s the .NET collection class that allows an element to be accessed using a unique key?
HashTable.

13. What class is underneath the SortedList class?
A sorted HashTable.

14. Will the finally block get executed if an exception has not occurred?
Yes.

15. What’s the C# syntax to catch any possible exception?
A catch block that catches the exception of type System.Exception. You can also omit the parameter data type in this case and just write catch {}.

16. Can multiple catch blocks be executed for a single try statement?
No. Once the proper catch block processed, control is transferred to the finally block (if there are any).

17. Explain the three services model commonly know as a three-tier application.
Presentation (UI), Business (logic and underlying code) and Data (from storage or other sources).

Related posts:

  1. SQL Interview Questions and Answers Here are some impotent question and answer which everyone should prepare before an interview SQL Interview Questions and Answers : What is the difference between oracle,sql and sql server ?...
  2. Frequently Asked Questions about MS-SQl server If you are going to face an interview then definitely my this blog can help you a lot. Be prepare with fallowing questions to be selected one . Why is...
  3. SAI’s choice of candidates for SDA raises questions The Sports Authority of India (SAI) has shortlisted two of its own candidates for an interview for the post of Sports Development Advisor to be based at Commonwealth Secretariat in...
  4. Spider catcher-To be in problem free zone It will help you catch the spiders and other insects easy and fast. When you push the button, it shoots out soft nylon bristles and catches the insect with it....

Leave a Response

You must be logged in to post a comment.