C# Coding Conventions

Our C# coding conventions are inspired from Google's Style Guide, and from the .NET Framework Design Guidelines.

Overview & Coding approach

• Keep lines short and not expand beyond the 90th column. Prefer short sentences as you would when writing free text.
• Respect your surroundings: make sure that you've established a good understanding of a project's conventions and follow them.
• Be "conservative" before introducing new technologies (libraries, frameworks etc) to a project. Be certain that it will further help development and achieve consent before you introduce them.
• Pierce through the abstraction layer of the things you use. Try and understand how your tools (libraries, frameworks etc) work.
• Pay attention when naming things. Be clear and concise.
• Examine your changes carefully before submitting your code (commit).
• Always code as if your code is meant to be read by someone else.

Programs are meant to be read by humans and only incidentally for computers to execute

Donald Knuth

Naming

• Use PascalCase for names of classes, methods, enumerations, public fields, public properties, namespaces.

• Names of interfaces start with I, e.g. IInterface.

• Use camelCase for names of local variables and function parameters.

• Prefix private class members/fields with underscore. E.g. private bool _myPrivateField.

• Use PascalCase for Filenames and directory names. E.g. MyFile.cs.

Namespaces

• Namespaces should be no more than 2 levels deep.
• Don't force file/folder layout to match namespaces.
• Top-level namespace names must be globally unique and recognizable.

New lines

Use a new line character before opening curly brackets ({}) only for classes, interfaces, structs & function bodies. Do not add new lines before opening brackets to if/else, for/foreach/while, class instantiations or anonymous types declarations.

Whitespace

• Add space after commas.
• Add a space character between:
  1. a unary operator and its operand.
  2. the operator and each operand of all other operators.
• Do not add spaces after an opening parenthesis or before a closing parenthesis.
• Line continuations are indented 4 spaces.
• No trailing spaces.

Example

// Bad
using System;
namespace projectName.src.domain.Services {
    public class Projectservice : iProjectService 
    {
        private readonly dBContext DBContext;

        public Projectservice(dBContext dbcontext)
        {
            DBContext = dbcontext;
        }

        public bool getStatus(bool status) { 
       
            if(status == null)
            {
                throw new ArgumentNullException(
                    nameof(status)
                    );
            }
        }
    }
}

// Good
using System;

// Keep XML comments as a visual aid, clearly separating
// members between one another (suggestion).
namespace ProjectName.Services
{
    /// <summary>
    /// 
    /// </summary>
    public class ProjectService : IProjectService
    {
        /// <summary>
        /// 
        /// </summary>
        private readonly DbContext _dbContext;

        /// <summary>
        /// 
        /// </summary>
        public bool Status { get; set; }

        /// <summary>
        /// 
        /// </summary>
        private bool _active { get; set; }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="dbContext"></param>
        public ProjectService(
            DbContext dbContext)
        {
            _dbContext = dbContext;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public void Save()
        { 
            try {
                if (_dbContext.SaveChanges() > 0 ) {
                    // no new lines to `if`s opening bracket
                } else {

                }
            } catch(Exception) {
                // log
            }
        }
    }
}

Async

• Prefer async methods where possible.
• Use async suffix to methods that return Task.

Example

// Bad
public async Task SendEmail(Options options);

// Good
public async Task SendEmailAsync(Options options);

Use var

• Use var instead of declaring the full type's name for simplicity.

Example

// Bad
List<Customer> customers = new List<Customer>();
bool customerExists = true;

// Good
var customers = new List<Customer>();
var customerExists = true;