.NET Interview Prep: 3 Fundamentals to Master

𝗠𝗮𝘀𝘁𝗲𝗿 𝗘𝗙 𝗖𝗼𝗿𝗲 𝘄𝗶𝘁𝗵 𝗜𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄𝘀 Want to ace your .NET interviews?  Here’s a common EF Core mistake many candidates make — practicing this can save you from tricky interview pitfalls! Working with Entity Framework Core in real projects is not just about writing code — it’s about writing it correctly and efficiently. This snippet highlights issues like improper database design, missing async calls, and skipping repository patterns — all critical for robust applications and technical interviews. Can you spot all the mistakes in this code? How would you fix it to follow async, repository, and proper EF Core best practices? #DotNet #EFCore #CSharp #CodingInterview #CodeReview #AsyncAwait #RepositoryPattern #SoftwareDevelopment #InterviewPrep #LearnDotNet

🚀 Day 6 — .NET Interview Prep Series Today’s topic: const vs readonly in C# This one looks simple — until the interviewer smiles and asks, “Okay… but when do you use which?” 😅 Let’s crack it 👇 🧊 const — Compile-time constant Value must be assigned at declaration Value cannot change — ever Stored in IL at compile time Only works with primitive types & strings Faster, but not flexible const int maxUsers = 100; Think of const like a tattoo — once written, no changes 🖊️❌ 🧱 readonly — Run-time constant Value can be assigned in constructor or declaration Can be different per object Perfect for reference types & dynamic values Evaluated at runtime readonly string env; public AppConfig(string environment) { env = environment; // allowed } readonly is like your apartment lease — fixed once you move in 🏡✅ 🧠 Interview Tip Use: ✅ const for fixed values like Pi, tax percentage, roles, app version ✅ readonly when value depends on runtime/config, like environment, connection strings, API keys Const = Permanently fixed Readonly = Fixed after initialization 💬 Tell me in comments — Where have you used readonly in your projects? 🙂 Tomorrow — async vs await or SOLID basics? Vote 👇🔥 #DotNet #CSharp #const #readonly #CodingTips #InterviewPrep #FullStackDeveloper

C# Interview question - Day 2/15 Understanding protected access modifier. What will be the output of this ? Will there be any errors ? public class A { protected int propertyA { get; set; } public A() { propertyA = 10; } } public class B: A { public void Show() { Console.WriteLine("propertyA value " + propertyA); A a = new A(); a.propertyA = 20; Console.WriteLine(a"propertyA value: " + propertyA); } } Explanation: propertyA is protected, so it can be accessed directly only in the base class or derived class. But here, a.propertyA = 20 tries to access it via an object of class A. That’s not allowed — C# will throw a compile-time error #CSharpInterview #Interview #accessModifier .

💡 Interview Tip: Local Storage vs Session Storage When interviewers ask about storage in JavaScript, they often test your real understanding through practical scenarios — not just definitions. 😖 🗃 Local Storage Persists even after browser close or system restart. Accessible across tabs and windows (same origin). Data persists until manually deleted. Synchronous in nature. Max limit ≈ 5MB. For large or async operations → use IndexedDB. Exceeding limit throws QuotaExceededException. 🕓 Session Storage Data is lost once the tab or window is closed. Not shared across tabs or windows. Persists only on page reload (within same session). Also synchronous, ≈ 5MB limit. For async and large data → again, IndexedDB is the answer. 🎯 Pro Tip: If they ask about storing big files (like images), mention QuotaExceededException and recommend IndexedDB — that’s the “expert” touch they look for.

💡 Interview Tip: Local Storage vs Session Storage When interviewers ask about storage in JavaScript, they often test your real understanding through practical scenarios — not just definitions. 😖 🗃 Local Storage Persists even after browser close or system restart. Accessible across tabs and windows (same origin). Data persists until manually deleted. Synchronous in nature. Max limit ≈ 5MB. For large or async operations → use IndexedDB. Exceeding limit throws QuotaExceededException. 🕓 Session Storage Data is lost once the tab or window is closed. Not shared across tabs or windows. Persists only on page reload (within same session). Also synchronous, ≈ 5MB limit. For async and large data → again, IndexedDB is the answer. 🎯 Pro Tip: If they ask about storing big files (like images), mention QuotaExceededException and recommend IndexedDB — that’s the “expert” touch they look for. Create 1:1 session with me on topmate: https://lnkd.in/gkhyGGf7

Think multiple await calls in your async method run in parallel? Think again, this topic caught me off guard in my recent interview. Interviewer : "In a .NET Core async method with multiple await statements, do the awaited tasks run in parallel or sequentially?" Honestly, I wasn’t able to answer it right away. I realized I hadn’t fully grasped an important detail about how async/await works with multiple task. Later, I dug into it and learned that if you write: await Task1(); await Task2(); the tasks actually run sequentially, not in parallel. Task2 won’t start until Task1 finishes. For true parallel execution, you have to start the tasks first and then await them all together: var t1 = Task1(); var t2 = Task2(); await Task.WhenAll(t1, t2); This allows them to run concurrently, improving performance significantly. This interview was a great learning moment for me, a reminder that even on topics you think you know, there’s always more to uncover. Be curious 🧐 #dotnet #csharp #async #interview #asynchronous #multithreading #devstories

🚀 Day 11 — .NET Interview Prep Series Today’s topic is something that instantly makes you sound senior in interviews 👇 Dependency Injection (DI) in .NET 💉⚙️ Don't worry — it’s not medical, though it does inject life into clean code 😌 🧠 What is Dependency Injection? In simple words: Dependency Injection is a design pattern where dependencies (services/classes) are given to a class instead of the class creating them. Why? To avoid code like this 👇 (aka hard dependency hell 😭) var service = new EmailService(); var user = new UserController(service); Instead — we let the framework supply dependencies automatically 🎁 🎯 Why DI? ✅ Loose coupling ✅ Better testability ✅ Reusable components ✅ Cleaner & maintainable code ✅ No “new-ing” everywhere In interviews, say: DI helps follow SOLID principles (esp. Dependency Inversion + Single Responsibility). Instant bonus points ✅😎 🧩 DI Types Constructor: Injectionvia constructor (most common ✅) Method Injection: via method parameters Property Injection: via public setters ⚙️ DI in .NET Core Example Register in Program.cs / Startup.cs builder.Services.AddScoped<IEmailService, EmailService>(); Inject in Controller public class AccountController : Controller { private readonly IEmailService _emailService; public AccountController(IEmailService emailService) { _emailService = emailService; } } Boom 💥 No manual object creation. Framework handles it. 🗂️ DI Lifetime Types Singleton: One instance per application Scoped: One instance per request Transient: New instance every time 🎧 Analogy Ordering coffee ☕: You don’t bring your own cup, machine, beans, milk Coffee shop “injects” everything to you You just request it 😎 DI is your coffee shop for class dependencies 💡 ✅ Interview Line DI decouples components, improves testability, and allows the framework to manage object creation through IoC (Inversion of Control) container. 💬 Comment below: Should Day 12 be Middleware, EF Core, or SOLID Principles? Let’s keep building this Dev muscle 💪🔥 #DotNet #CSharp #DependencyInjection #IoC #SoftwareArchitecture #InterviewPrep #FullStackDeveloper

💻 Master Your C# Interview Questions — Brush Up Like a Pro! . . Are you preparing for a .NET or C# technical interview? Here are some real-world C# interview questions that test both your fundamentals and practical understanding 👇 🔹 Do you know the difference between Method Overriding, Method Overloading, and Method Hiding? 🔹 What is the Task Parallel Library (TPL) in .NET? 🔹 Difference between Thread and Task? 🔹 What’s the use of Global.asax.cs file in ASP.NET? 🔹 Difference between ==, ===, and .Equals()? 🔹 Why does it matter whether you place a script in the Header vs Body tag? 🔹 What is a Private Virtual Method? 🔹 Difference between Array and ArrayList, and between List and ArrayList. 🔹 What happens when you perform dynamic initialization on two variables — what error do you get and why? 🔹 Explain Session Modes in ASP.NET — InProc, OutProc, and steps to create a session object. 🔹 What is AutoPostBack and when should you use it? . These are the kinds of questions that not only test syntax — but your conceptual clarity and practical application. 👉 Whether you’re preparing for interviews or brushing up your skills, these are must-know concepts for every C# developer. Let’s discuss in the comments — follow for more stuff : https://lnkd.in/d3_dBT2c 💬 Which question do you find most tricky or interesting? #CSharp #DotNet #DotNetDeveloper #TechnicalInterview #CodingInterview #SoftwareDevelopment #LearnCSharp #BackendDevelopment #InterviewPreparation #AspNet #Programmer

🚀 .NET Interview Prep – Dependency Injection Explained If you are preparing for .NET interviews, Dependency Injection (DI) is one concept you must understand DI helps us write loosely coupled, testable, and clean code by providing dependencies from outside rather than creating them inside a class. I explained this in a very simple and clear way in this short video 👇 🎥 https://lnkd.in/g8R5Te3m If you're preparing for .NET or want to improve your understanding of clean architecture, this will help you. #dotnet #csharp #interviewpreparation #softwaredevelopment #programming #learncoding #cleanarchitecture

🚀 Day 802 of #900DaysOfCode 🎯 5 Must-Know Local Storage Interview Questions Local Storage might seem like a small topic — but interviewers love testing your understanding of it because it reveals how deeply you know the browser environment. In today’s post, I’ve shared 5 of the most commonly asked Local Storage interview questions, along with clear and concise explanations that will help you tackle them confidently. If you’re preparing for a frontend or full-stack interview, these questions are a must-revise before you step in! 💬 How comfortable are you with Local Storage concepts? Drop your thoughts in the comments 👇 #Day802 #900DaysOfCode #FrontendDevelopment #WebDevelopment #JavaScript #InterviewPreparation #CodingCommunity #LocalStorage #BrowserStorage #CodingJourney