# Esensi Bahasa C# (.NET)

> Nullable types, generics, attributes, extension methods, type casting, enum lanjutan

- 15 pertanyaan wawancara
- Junior
- [Pertanyaan Wawancara: .NET](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara.md)

## 1. Apa sintaks yang benar untuk mendeklarasikan variabel nullable int di C#?

**Jawaban**

Dalam C#, nullable type untuk value types dideklarasikan dengan akhiran '?' setelah tipe (int?, bool?, DateTime?). Ini memungkinkan value types memiliki nilai null, yang secara default tidak mungkin. Nullable types berguna untuk merepresentasikan ketiadaan nilai dalam skenario database atau API.

## 2. Operator mana yang memungkinkan menyediakan nilai default jika variabel nullable bernilai null?

**Jawaban**

Operator null-coalescing '??' mengembalikan nilai sebelah kiri jika tidak null, jika tidak nilai sebelah kanan. Operator ini sangat berguna untuk menangani nullable types dan menghindari NullReferenceException. Ada juga operator '??=' untuk penugasan kondisional yang diperkenalkan di C# 8.

## 3. Apa perbedaan antara casting dengan '(Type)' dan 'as' di C#?

**Jawaban**

Cast '(Type)object' melempar InvalidCastException jika konversi gagal, sementara operator 'as' mengembalikan null saat gagal. Operator 'as' hanya bekerja dengan reference types dan nullable value types. Gunakan 'as' untuk menghindari eksepsi dalam kasus di mana null adalah nilai yang dapat diterima.

## 12 pertanyaan lagi tersedia

- Bagaimana cara memeriksa apakah variabel nullable memiliki nilai sebelum menggunakannya?
- Apa sintaks untuk mendeklarasikan kelas generik dengan batasan tipe?

Daftar gratis: https://sharpskill.dev/id/login

## Topik wawancara .NET lainnya

- [Dasar-Dasar C#](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/csharp-basics.md): 25 pertanyaan, Junior
- [LINQ & Delegates](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/csharp-linq-delegates.md): 20 pertanyaan, Junior
- [Dasar-Dasar ASP.NET Core](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/aspnet-core-fundamentals.md): 18 pertanyaan, Junior
- [Siklus Hidup Request ASP.NET Core](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/aspnet-core-request-lifecycle.md): 20 pertanyaan, Junior
- [Configuration & Settings](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/configuration-settings.md): 20 pertanyaan, Junior
- [Siklus Hidup Aplikasi](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/application-lifecycle.md): 20 pertanyaan, Junior
- [Dependency Injection](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/dependency-injection.md): 24 pertanyaan, Mid-Level
- [Entity Framework Core](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/entity-framework-core.md): 25 pertanyaan, Mid-Level
- [Minimal APIs](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/minimal-apis.md): 18 pertanyaan, Mid-Level
- [Pengembangan Web API](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/web-api-development.md): 22 pertanyaan, Mid-Level
- [Async di ASP.NET Core](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/async-aspnet-core.md): 20 pertanyaan, Mid-Level
- [Authentication & Authorization](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/authentication-authorization.md): 18 pertanyaan, Mid-Level
- [HttpClient & Networking](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/httpclient-networking.md): 20 pertanyaan, Mid-Level
- [Serialisasi JSON](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/json-serialization.md): 20 pertanyaan, Mid-Level
- [Entity Framework Core Tingkat Lanjut](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/ef-core-advanced.md): 25 pertanyaan, Mid-Level
- [Fitur Lanjutan C#](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/csharp-advanced-features.md): 20 pertanyaan, Mid-Level
- [Clean Architecture](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/clean-architecture.md): 20 pertanyaan, Mid-Level
- [Logging, Monitoring & Observability](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/logging-monitoring.md): 22 pertanyaan, Mid-Level
- [Unit Testing & xUnit](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/unit-testing-xunit.md): 20 pertanyaan, Mid-Level
- [Pengujian Integrasi](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/integration-testing.md): 18 pertanyaan, Mid-Level
- [Docker & Containerization](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/docker-containerization.md): 16 pertanyaan, Mid-Level
- [Manajemen Paket NuGet](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/nuget-package-management.md): 16 pertanyaan, Mid-Level
- [Memory Management & GC](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/memory-management-gc.md): 22 pertanyaan, Senior
- [Pemrograman reaktif](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/reactive-programming.md): 24 pertanyaan, Senior
- [Async/await & Pola](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/async-await-patterns.md): 26 pertanyaan, Senior
- [.NET Design Patterns](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/dotnet-design-patterns.md): 24 pertanyaan, Senior
- [Optimasi Performa](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/performance-optimization.md): 22 pertanyaan, Senior
- [Keamanan & Best Practices](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/security-best-practices.md): 24 pertanyaan, Senior
- [SignalR & Real-time](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/signalr-realtime.md): 22 pertanyaan, Senior
- [Arsitektur Microservices](https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/microservices-architecture.md): 25 pertanyaan, Senior

---

Source: SharpSkill (https://sharpskill.dev), tech interview preparation for your real stack.
HTML version of this page: https://sharpskill.dev/id/technologies/dotnet/pertanyaan-wawancara/csharp-language-essentials