C# Coding Standard: Variables

01 November, 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. Below, I present the guidelines for Variables in accordance with C# coding standards that I rigorously apply in my projects.

Variables :

Naming:

Variable names should be concise and representative of nature and the quantity of the value it holds or will potentially hold.

Names:

                           var employee = new Employee();
                    

The same rule applies to lambda expressions:

                           employees.Where(employee => employee ... );
                    

Plurals:

                           var employees = new List<Employee>();
                    

Names with Types:

                           var employee = new Employee();
                    

Nulls or Defaults:

If a variable value is it's default such as 0 for int or null for strings and we are not planning on changing that value (for testing purposes for instance) then the name should identify that value.

                          Employee noEmployee = null;
                    

or

                          int noChangeCount = 0;
                    

Declarations

Declaring a variable and instantiating it should indicate the immediate type of the variable, even if the value is to be determined later.

Clear Types

If the right side type is clear, then use var to declare our variable

                     var employee = new Employee();
                    

Semi-Clear Types

If the right side isn't clear (but known) of the returned value type, then we must explicitly declare our variable with it's type.

                     Employee employee = GetEmployee();
                    

Unclear Types

If the right side isn't clear and unknown (such as an anonymous types) of the returned value type, we may use var as your variable type.

                        var employee = new
                            {
                                Name = "Rana",
                                Salary = 5000
                            };
                    

Single-Property Types

Assign properties directly if we are declaring a type with one property.

                          var inputEmployeeEvent = new EmployeeEvent();
                          inputEmployeeEvent.Employee = inputProcessedEmployee;
                    

or

                      var employeeEvent = new EmployeeEvent
                            {
                                Employee = someEmployee,
                                Date = someDate
                            }
                    

Breakdown

If a variable declaration exceeds 120 characters, break it down starting from the equal sign.

                     List<Employee> ItDepartmentsEmployeesWithSalaries =
                     await GetAllItDepartmentsEmployeesWithSalariesAsync();
                    

Multiple Declarations

Declarations that occupy two lines or more should have a new line before and after them to separate them from previous and next variables declarations.

                        Employee employee = GetEmployee();

                      List<Employee>  ItDepartmentsEmployeesWithSalaries =
                            await GetAllItDepartmentsEmployeesWithSalariesAsync();

                        Department department = await GetDepartmentAsync();
                    

Also, declarations of variables that are of only one line should have no new lines between them.

                           Employee employee = GetEmployee();
                           Department department = await GetDepartmentAsync();
                    

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