clean-code-dotnet

Clean Code .NET

Clean Code principles from Robert C. Martin, adapted for C#/.NET. Use as checklist during code reviews and refactoring.

Naming

Use Meaningful Names

// ❌ Bad
int d;
var dataFromDb = db.GetFromService().ToList();

// ✅ Good
int daySinceModification;
var employees = _employeeService.GetEmployees().ToList();

Avoid Hungarian Notation

// ❌ Bad
int iCounter;
string strFullName;
public bool IsShopOpen(string pDay, int pAmount) { }

// ✅ Good
int counter;
string fullName;
public bool IsShopOpen(string day, int amount) { }

Use Pronounceable Names

// ❌ Bad
public class Employee
{
    public DateTime sWorkDate { get; set; }
    public DateTime modTime { get; set; }
}

// ✅ Good
public class Employee
{
    public DateTime StartWorkingDate { get; set; }
    public DateTime ModificationTime { get; set; }
}

Use Domain Names

// ✅ Good - Use patterns developers know
var singletonObject = SingleObject.GetInstance();
var factory = new PatientFactory();
var repository = new PatientRepository();

---

Variables

Return Early, Avoid Deep Nesting

// ❌ Bad - Deep nesting
public bool IsShopOpen(string day)
{
    if (!string.IsNullOrEmpty(day))
    {
        day = day.ToLower();
        if (day == "friday")
        {
            return true;
        }
        else if (day == "saturday")
        {
            return true;
        }
        // ... more nesting
    }
    return false;
}

// ✅ Good - Guard clauses + early return
public bool IsShopOpen(string day)
{
    if (string.IsNullOrEmpty(day))
        return false;

    var openingDays = new[] { "friday", "saturday", "sunday" };
    return openingDays.Contains(day.ToLower());
}

Avoid Magic Strings

// ❌ Bad
if (userRole == "Admin") { }

// ✅ Good
const string AdminRole = "Admin";
if (userRole == AdminRole) { }

// ✅ Better - Use enum
public enum UserRole { Admin, User, Guest }
if (userRole == UserRole.Admin) { }