TOP 100 Interview Questions and Answers for .NET Developer

Q.1 What is SOLID Principle 

Ans. In the Object-Oriented Programming (OOPS), SOLID is an acronym, introduced by Micheal Feather, for five Design principles used to make software design more understandable, flexible, and maintainable. These principles are a subset of many other principles promoted by Robert C. Martin.

There are Five SOLID Principles
1.Single Responsibility Principle (SRP).
2.Open-Closed Principle (OCP).
3.Liskov Substitution Principle (LSP).
4.Interface Segregation Principle (ISP).
5.Dependency Inversion Principle (DIP).

Q.2 What is boxing and unboxing 

Ans. Boxing and Unboxing in C# Programming

Boxing is a mechanism converting value type to object type 

int j = 123;

// The following line boxes i.

object o = j;

Unboxing is an explicit conversion from the type object to a value type or from an interface
type to a value type

int j = 123;      // a value type

object o = j;     // boxing

int k = (int)o;   // unboxing

Q.3 What is the difference between asp.net c# and mvc.?

ASP.NET framework is a part of .net platform for building, deploying and running
web applications. Now, we can develop a web application by using Asp.Net Web Form
and Asp.Net MVC. In this article, I am going to expose the main difference between
ASP.NET WebForms and ASP.NET MVC.

Difference between ASP.NET MVC and WebForms

Asp.Net Web Forms	Asp.Net MVC
Asp.Net Web Form follow a traditional event-driven development model.	Asp.Net MVC is a lightweight and follows MVC (Model, View, Controller) pattern based development, model.
Asp.Net Web Form has server controls.	Asp.Net MVC has HTML helpers.
Asp.Net Web Form supports view state for state management at the client-side.	Asp.Net MVC does not support view state.
Asp.Net Web Form has file-based URLs means file name exists in the URLs must have its physical existence.	Asp.Net MVC has route-based URLs means URLs are divided into controllers and actions and moreover it is based on controller not on physical file.
Asp.Net Web Form follows Web Forms Syntax	Asp.Net MVC follow customizable syntax (Razor as default)
In Asp.Net Web Form, Web Forms (ASPX) i.e. views are tightly coupled to Code behind(ASPX.CS) i.e. logic.	In Asp.Net MVC, Views and logic are kept separately.
Asp.Net Web Form has Master Pages for a consistent look and feels.	Asp.Net MVC has Layouts for a consistent look and feels.
Asp.Net Web Form has User Controls for code re-usability.	Asp.Net MVC has Partial Views for code re-usability.
Asp.Net Web Form has built-in data controls and best for rapid development with powerful data access.	Asp.Net MVC is lightweight, provide full control over markup and support many features that allow fast & agile development. Hence it is best for developing an interactive web application with the latest web standards.
Asp.Net Web Form is not Open Source.	Asp.Net Web MVC is an Open Source.