Usually C# interview questions for experienced professionals are specifically structured to elicit more targeted responses and garner better insights.
This is done with the intent of determining whether you are the best fit for the job on offer.
List of 8 C# Interview Questions
1. How would you implement the Singleton design pattern in C#?
There are numerous ways to implement Singleton in C#:
• Standard Singleton Implementation
• Early Instance Creation
• Double Checked Locking
• Using Generics
• Fully Lazy Instantiation
• Using Lazy type
2. Describe the Async method of C#?
Async (asynchronous programming) can be described as a method that returns to the calling method before finishing its work fully. It then proceeds to complete its work while the calling method goes along with its execution.
3. What is an Object?
An object is an instance of a class and comprises of real values as opposed to variables. For instance, say we were to create an instance of the class Employee called “Raj”.
Employee Raj = new Employee();
We will now be able to access all the methods in the class “Employee” via object “Raj” as given below.
Raj.setName(“XYZ”);
4. Is it possible to serialise hashtables?
It is not possible to serialise hashtables – a collection of key-value pairs – as the .NET Framework prevents serialisation of any object that implements the IDictionary interface. The XmlSerializer class will display an error when an attempt is made to serialise a Hashtable.
5. Explain the differences between “out” and “ref” parameters in C#?
Although quite similar, the “out” parameter can be passed to a method and doesn’t require to be initialised whereas the “ref” parameter has to be initialised and set to something before it is used.
6. Can you explain the concept of inner exception in C#?
An inner exception can be described as a property of exception class which gives you a brief understanding of the exception, i.e., details on the parent exception as well as the child exception.
7. Explain the use of the System. Environment class in C#.NET.
The System. Environment class provides all relevant information about the current environment and platform. It can also be used to retrieve information such as:
a. Command-line arguments
b. The exit code
c. Environment variable settings
d. Contents of the call stack
e. Time since last system boot
f. The version of the common language runtime
Further, if you’re looking to retrieve environment variable settings, version of the common language runtime, etc., the System, environment class can help you do so.
8. Explain what is Namespaces in C#.
In C#, Namespaces are usually used to organise and provide a level of separation of codes. Indicated by the keyword “namespace,” they can also be put to use to compose substantial code ventures.
Looking for more examples of some popular C# interview questions that are likely to be asked in your interview? We have compiled an additional list of questions that can be thrown in your direction during your interview so make sure not to be caught off-guard.
• Can you explain the difference between the “throw” and “throw ex” in .NET?
• How does C# handle encapsulation?
• Explain the use of GetCommandLineArgs() method in C#.NET?
• What is Abstract Class in C#?
• Describe the use of Virtual Keyword in C#?
• How to create a custom exception in C# .net program? Describe its use.
• Describe method hiding in C# inheritance? Explain its uses with an example.
• What would you choose between the C# interface and abstract class?
• Can you shed light on what delegates are in C# Programming?
• Why is the singleton pattern considered to be an anti-pattern?
• Elaborate on the differences between shadow and override?
Last but not the least, do note that once your interview is over, you should ideally have a list of questions for your interviewer. This not only helps you find out more about the job you’re applying for but also helps your potential employer justify their decision of calling you in for the interview.
All the best!
