100 C# Tips I Wish I Knew Earlier (Part 1)

Source: Dev.to

Modern C# Features That Improve Your Code

1. Embrace Primary Constructors

public class Person(string name, int age)
{
    public string Name { get; } = name;
    public int Age { get; } = age;
}

Cleaner, shorter, and easier to maintain.

2. Use Collection Expressions

List numbers = [1, 2, 3, 4, 5];

Less typing, more clarity.

3. Use nameof for Safer Refactoring

Console.WriteLine(nameof(Person.Name));

The compiler now helps you catch mistakes.

4. Use Null‑Coalescing for Safer Code

string name = person.Name ?? "Unknown";

Simple and safe.

5. Pattern Matching = Cleaner Logic

if (person is { Age: > 18, Name: not null })
{
    Console.WriteLine($"{person.Name} is an adult.");
}

6. Prefer String Interpolation

string message = $"Hello, {person.Name}!";

7. Use Tuples Instead of Extra Classes

public (string, int) GetPersonInfo()
{
    return ("Alice", 30);
}

Lightweight and efficient.

8. Use Local Functions for Better Structure

void Process()
{
    int Add(int a, int b) => a + b;
    Console.WriteLine(Add(1, 2));
}

9. Use using var Instead of Nested Blocks

using var reader = new StreamReader("file.txt");

Cleaner resource management.

10. Use IAsyncEnumerable for Streaming Data

public async IAsyncEnumerable GetData()
{
    for (int i = 0; i
}

Switch Statements

string result = age switch
{
    > 18 => "Adult",
    _    => "Minor"
};

14. Use with for Object Updates

var updated = person with { Age = 31 };

15. File‑Scoped Namespaces Reduce Noise

namespace MyApp;

Cleaner files instantly.

16. Use required for Safer Models

public class Person
{
    public required string Name { get; set; }
}

17. Init‑Only Properties for Immutability

public string Name { get; init; }

18. Global Using Saves Repetition

global using System;

19. CallerArgumentExpression for Debugging

public void Validate(bool condition,
    [CallerArgumentExpression("condition")] string msg = "")
{
    if (!condition) throw new Exception(msg);
}

20. Default Interface Methods

public interface ILogger
{
    void Log(string msg) => Console.WriteLine(msg);
}

Performance & Advanced Tips

21. Use Span for High Performance

Span numbers = stackalloc int[10];

22. Use ArrayPool to Reduce GC Pressure

var pool = ArrayPool.Shared;
var arr = pool.Rent(10);
pool.Return(arr);

23. Use ValueTask for Lightweight Async

public ValueTask GetValueAsync() => new(42);

24. ConfigureAwait for Better Performance

await Task.Delay(100).ConfigureAwait(false);

25. Use Stopwatch to Measure Performance

var sw = Stopwatch.StartNew();
// code to measure
sw.Stop();
Console.WriteLine(sw.ElapsedMilliseconds);

Final Thoughts

These small improvements compound over time.

They made my code:

• Cleaner
• Faster
• Easier to maintain