C# Coding Standard: Classes and Interfaces

01 August, 2023

READ TIME - 5 MINUTES

Introduction:

I consistently strive to adhere to the highest coding standards and adopt a pragmatic approach in my software development endeavors. Presented below are the guidelines for classes and interfaces as per the C# coding standards that I rigorously apply in my projects. I keep all the classes' modifiers public intentionally, but it depends on the specific requirements.

Classes :

Model Name should be Singular.

Models :

                       public class Employee
                       {
                          ...
                          ...
                       }
                   

Repositories :

                       public class EmployeeRepository
                       {
                          ...
                          ...
                       }
                   

Services :

                       public class EmployeeService
                       {
                          ...
                          ...
                       }
                   

Interfaces :

Every Interface should be start with capital letter I

                       public interface IEmployeeService
                       {
                          ...
                          ...
                       }
                   

Controllers :

In a plural fashion, to reflect endpoints such as /api/employees to expose our logic via RESTful operations.

                       public class EmployeesController
                       {
                          ...
                          ...
                       }
                   

Fields :

A field is a variable of any type that is declared directly in a class or struct. Fields are members of their containing type.

Naming :

Class fields are named in a camel cased fashion.

                       public class EmployeesController
                       {
                          private readonly string EmployeeName;
                       }
                   

Referencing :

When referencing a private field, we can use the following approach.

                       public class EmployeesController
                       {
                            private readonly string _employeeName;

                            public EmployeesController(string employeeName)
                            {
                              _employeeName = employeeName;
                            }
                       }
                   

                        public class EmployeeRepository : IEmployeeRepository
                        {
                            private readonly ApplicationDbContext _context;
                            public EmployeeRepository(ApplicationDbContext context)
                            {
                                _context = context;
                            }
                        }
                   

Instantiations :

Input Params Aliases :

If the input variable names match the input aliases, then we can use them; otherwise, we must use the aliases, especially with values passed in.

                        int score = 95;
                        string name = "Saddam Hossain";

                        var employee = new Employee(name, score);
                   

Property Order :

When instantiating a class instance - make sure that our property assignment matches the properties order in the class declarations.

                        public class Employee
                        {
                            public Guid Id {get; set;}
                            public string Name {get; set;}
                        }

                        var employee = new Employee
                        {
                            Id = Guid.NewGuid(),
                            Name = "Rana"
                        }
                   

Alternatively, we can define it this way.

                        public class Employee
                        {
                            private readonly Guid _id;
                            private readonly string _name;

                            public Employee(Guid id, string name)
                            {
                                _id = id;
                                _name = name;
                            }
                        }

                        var employee = new Employee (_id: Guid.NewGuid(), _name: "Rana");
                   

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