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C# & .NET, revised properly

Everything a senior .NET Web API interview asks — in plain language, with real C# examples. 299 questions across 16 modules, grouped into 5 categories so you can revise just the part you need, plus a cheat sheet and flashcards for the last hour.

0 of 15 modules done

How to use this

The fast route

Pick a category in the sidebar — it expands to show only its modules, so revising C# doesn't drown you in EF Core. In each module, the big questions have a 30-second interview answer box: that's the bit to read out loud. The compact rows are there so you recognise the term if it comes up.

If you have…Do this
3 daysOne category per day: A+B, then C, then D+E. Flashcards each evening.
1 dayModules 05, 07, 09, 10, 11, 13 — async, LINQ, EF Core, pipeline, API design, patterns.
3 hoursCheat sheet → flashcards → the Trap boxes only.
30 minutesCheat sheet, printed. The "20 things to be sure of" table twice.

Two kinds of question

Deep questions (124 of them) get the full treatment: a one-line answer, a diagram or comparison table, C# code, the trap interviewers probe for, and a ready-to-speak 30-second answer. Compact questions are a tight box — the answer in a few lines plus a snippet — so a module stays quick to scan.

Predict the output

Where C# behaves surprisingly — string interning, boxing, throw vs throw ex, deferred execution, .Result deadlocks — you'll get the code with a hidden answer. Work it out first, then click Show the answer. Every code block also has a Copy button, so you can paste it into Visual Studio and run it for real.

Search

The sidebar search covers all 299 questions from any page — try "boxing", "captive", "idempotent", "N+1". Results link straight to the answer.