.Net developers seeking jobs not only have to prep for interview questions related to their programming language skills, but also must prepare to showcase their abilities when it comes to Microsoft's .Net framework. Knowing which questions - and their relevant answers - will help you keep a leg up on the competition. In this article, we look at some of the most commonly asked questions during interviews for .Net developers and programmers.
Before we dive into our .Net Q&A session, there are a few general guidelines you should know that can help you during the interview session. For starters, employer's will expect you to know basic "best of" software development practices. They will also present you with programming terms or concepts and ask you to explain them in your own words. Sample code snippets and coding "puzzles" may also be presented to you; you will need to explain the intention of the code or solve the issue of the code in the puzzle.
While positions vary greatly, there are some basic requirements expected of every .Net software engineer - no matter the size of the company you are attempting to join. Some of those expectations include:
- Being able to debug and troubleshoot common issues with code and applications.
- Demonstrate solid programming best practices.
- Write clean and efficient code Understand and be proficient in one or more languages.
- Working knowledge of the .Net Framework.
- Know the concepts of Object-Oriented Programming (OOP).
- Be able to perform database queries using Microsoft SQL.
Job Interview Question for .Net Programmers
The following list of interview questions is by no means a complete list, nor are the questions listed here necessarily going to be asked; they are commonly posed during .Net interviews. As such, you should refresh your knowledge of .Net and the programming languages you know, as well as the core concepts of those technologies.
Question: What is the .Net framework and what are its core components?
Answer: The .Net framework is a developer platform that lets programmers build applications on Windows. It consists of built-in Classes, libraries, and APIs that you can use to create, deploy, and execute applications, software, and web services using languages including C#, F#, and Visual Basic. The application framework includes components such as the .Net Class library, Common Type System, Common Language Runtime, Application Domain, Profiling, and the .Net Framework.
Question: What is the .Net Framework Class Library?
Answer: The .Net Framework Class Library is made up of classes, interfaces, namespaces, and value types. This collection features thousands of classes that allow for functions like creating Windows-bas Graphical User Interfaces (GUI), developer web services, client-server apps, accessing data, exception handling, and many more.
Question: What is the Common Type System (CTS) in .Net?
Answer: .Net's Common Type System - or CTS - is a group of rules dictating how data types are declared and defined. It also dictates how data types are used in programs and the data types that will be used in your software. The CTS provides rules that are used for creating classes and their related values. Further, CTS ensures that any data type you declare with one programming language may be called by another application using a different language than the one you originally declared your data types with.
Question: What is the Common Language Runtime (CLR) in .Net?
Answer: The Common Language Runtime - also known as CLR - is responsible for the execution of .Net programs and is known as the virtual machine part of the .Net Framework. In addition to managing application execution, CLR also allows for exception handling, garbage collection, memory management, thread management, and type safety. In simpler terms, CLR takes code written in .Net programming languages and converts it into native code before passing it onto the CPU for execution.
Question: What is managed code?
Answer: Managed code is a term that was originally coined by Microsoft and describes .Net code that is architecture independent; managed code is executed by the Common Language Runtime (CLR), as opposed to the user's operating system. CLR takes managed code, compiles it into machine language, then runs it. It has the added benefit of services provided by the CLR that handle memory management, type safety, garbage collection, memory management, and other features of the CLR virtual machine.
Question: What is unmanaged code?
Answer: Unmanaged code, as you might suspect, is the opposite of managed code. Instead of getting executed by the Common Language Runtime, unmanaged code gets executed by the operating system of the user's machine. Because of this, unmanaged code does not benefit from the features of CLR and thus, software developers must handle tasks like memory allocation and exception handling on their own.
Question: What is Object Oriented Programming (OOP)?
Answer: Object-oriented programming (OOP) is a software development concept that uses four basic principles: Abstraction, Encapsulation, Inheritance, and Polymorphism. OOP uses Classes and Objects to create and model program structures that are simple and reusable, easy to debug, and secure.
Question: What is the difference between a Class and an Object?
Answer: Classes are basically a blueprint or a template used to create or define an Object. Classes describe the methods and properties of an Object. Objects, meanwhile, are instances of classes. Objects are able to access properties and methods from the class that defined them.