Online C# Compiler Features
Modern C# Language Features
- C# 12 with latest syntax improvements—primary constructors, collection expressions, and enhanced pattern matching
- Nullable reference types prevent null errors—use ? annotations for safer, more predictable C# code
- Record types for immutable data—create value-based equality classes with minimal boilerplate
- Pattern matching switch expressions—write cleaner conditional logic with exhaustive pattern checking
LINQ & Functional Style
- LINQ query expressions transform collections—filter, map, group, and join data with readable syntax
- Lambda expressions and delegates—create inline functions for callbacks, predicates, and functional composition
- Method chaining with extension methods—fluent APIs using .Where(), .Select(), .OrderBy() patterns
- Async/await for asynchronous code—practice modern async patterns without blocking operations
Strong Type System
- Compile-time type checking catches errors early—no runtime surprises from type mismatches
- Generics with constraints—build reusable, type-safe collections and algorithms with List
, Dictionary - Implicit typing with var keyword—let compiler infer types while maintaining type safety
- Tuple types for multiple return values—return structured data without creating dedicated classes
Professional Development Platform
- Perfect for C# interview preparation—test algorithms, OOP concepts, and LINQ queries instantly
- Learn enterprise patterns—practice dependency injection concepts, interfaces, and design patterns
- Share C# code snippets with colleagues—ideal for code reviews, tutorials, or documentation examples
- No .NET SDK installation needed—code C# immediately without configuring development environments
C# Keyboard Shortcuts
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This entire C# compiler was built by Replit Agent 3 from a natural language prompt. Replit's environment facilitates rapid development, iteration and testing code for users of any technical ability. Develop software faster and better with Replit’s autonomous AI.
Get started freeFrequently Asked Questions
What C# version does this online compiler support?
This C# compiler supports C# 12, the latest version with modern features like primary constructors, collection expressions, default lambda parameters, and enhanced pattern matching. Write professional C# code with cutting-edge language syntax.
Can I use LINQ in this C# online compiler?
Absolutely! Full LINQ support is available including query syntax, method chaining, lambda expressions, and all standard LINQ operators (Where, Select, OrderBy, GroupBy, Join, etc.). Perfect for practicing data transformations and functional programming patterns.
Does this support async/await keywords?
Yes, async and await keywords are supported. You can practice asynchronous code patterns, though actual I/O operations (file access, network calls) have limited browser support. Focus on understanding async syntax and Task-based programming.
Can I define multiple classes in C#?
Yes! Define as many classes, interfaces, structs, and enums as needed in a single file. Just ensure one class contains a static Main method as the entry point. Perfect for testing object-oriented design patterns and class hierarchies.
What .NET libraries are available?
This C# online compiler includes the .NET Standard Library with System namespace, collections (List, Dictionary, HashSet), LINQ, System.Text, System.IO basics, and core functionality. External NuGet packages aren't supported—focus on core C# and standard library features.
Is this good for C# interview preparation?
Perfect for interviews! Test algorithms, data structures, LINQ queries, OOP concepts, and design patterns instantly. Share C# solutions via URLs for portfolio demonstrations or interview follow-ups. Practice common interview questions without local setup.
Can I use nullable reference types?
Yes! C# 12 includes nullable reference types. Use ? annotations for nullable types and enjoy compiler warnings for potential null reference errors. Practice writing safer C# code with modern null-safety features.
How does C# compilation work in the browser?
Your C# code goes through full compilation to Intermediate Language (IL), just like Visual Studio. You'll see compile-time errors for syntax issues, type mismatches, and missing references before execution. Runtime errors include stack traces for debugging.
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