C# Coding Guideline

C# is a general-purpose, modern and object-oriented programming language pronounced as “C Sharp”. It was developed by Microsoft led by Anders Hejlsberg and his team within the .NET initiative and was approved by the European Computer Manufacturers Association (ECMA) and International Standards Organization (ISO). C# is among the languages for Common Language Infrastructure. C# is a lot similar to Java syntactically and is easy for users who have knowledge of C, C++, or Java.

Below are some of the best practices which all the .Net Developers should follow:

Class and Method names should always be in Pascal Case

public class Employee
{
    public Employee GetDetails()
    {
        //...
    }
    public double GetBonus()
    {
        //...
    }
}

Method argument and Local variables should always be in Camel Case

public class Employee
{
    public void PrintDetails(int employeeId, String firstName)
    {
        int totalSalary = 2000;
        // ...
    }
}

Avoid the use of underscore while naming identifiers

// Correct
int employeeId;
string employeeName;
bool isActive;


// Avoid
Int32 employee_id;
String employee_name;
Boolean is_active;

Always prefix an interface with letter I.

// Correct
public interface IEmployee
{
}
public interface IShape
{
}
public interface IAnimal
{
}

// Avoid
public interface Employee
{
}
public interface Shape
{
}
public interface Animal
{
}

For better code indentation and readability always align the curly braces vertically.

// Correct
class Employee
{
    static void PrintDetails()
    {
    }
}


// Avoid
class Employee
    {
    static void PrintDetails()
    {
      }
}

Always use the using keyword when working with disposable types. It automatically disposes the object when program flow leaves the scope.

using(var conn = new SqlConnection(connectionString))
{
    // use the connection and the stream
    using (var dr = cmd.ExecuteReader())
    {
     //
    }
}

Always declare the variables as close as possible to their use.

// Correct
String firstName = "Shubham";
Console.WriteLine(firstName);
//--------------------------
ExampleFunction();
AnotherFunction();
AnotherBusinessLogic();


// Avoid
String firstName = "Shubham";
ExampleFunction();
AnotherFunction();
AnotherBusinessLogic();
Console.WriteLine(firstName);

Always declare the properties as private so as to achieve Encapsulation and ensure data hiding.

// Correct
private int employeeId { get; set; }

// Avoid
public int employeeId { get; set; }

Always seperate the methods, different sections of program by one space.

// Correct
class Employee
{
	private int employeeId { get; set; }

	public void PrintDetails()
	{
	//------------
	}
}

// Avoid
class Employee
{

	private int employeeId { get; set; }



	public void PrintDetails()
	{
	//------------
	}

}

Constants should always be declared in UPPER_CASE.

// Correct
public const int MIN_AGE = 18;
public const int MAX_AGE = 60;

// Avoid
public const int Min_Age = 18;
public const int Max_Age = 60;

Use singular names for enums. Exception: bit field enums.

// Correct
public enum Color
{
    Red,
    Green,
    Blue,
    Yellow,
    Magenta,
    Cyan
}

// Exception
[Flags]
public enum Dockings
{
    None = 0,
    Top = 1,
    Right = 2,
    Bottom = 4,
    Left = 8
}

// Avoid
public enum Cars //Plural
{
    Bugatti,
    Ferrari,
    Ford,
    Audi,
    BMW
}

Naming Convention Examples

Language element	Casing	Example
Namespace	Pascal	`System.Drawing`
Type parameter	Pascal	`TView`
Interface	Pascal	`IBusinessService`
Class, struct	Pascal	`AppDomain`
Enum	Pascal	`ErrorLevel`
Enum member	Pascal	`FatalError`
Resource key	Pascal	`SaveButtonTooltipText`
Constant field	Pascal	`MaximumItems`
Private static readonly field	Pascal	`RedValue`
Private field	Camel	`listItem`
Non-private field	Pascal	`MainPanel`
Property	Pascal	`BackColor`
Event	Pascal	`Click`
Method	Pascal	`ToString`
Local function	Pascal	`FormatText`
Parameter	Camel	`typeName`
Tuple element names	Pascal	`(string First, string Last) name = ("John", "Doe");` `var name = (First: "John", Last: "Doe");` `(string First, string Last) GetName() => ("John", "Doe");`
Variables declared using tuple syntax	Camel	`(string first, string last) = ("John", "Doe");` `var (first, last) = ("John", "Doe");`
Local variable	Camel	`listOfValues`

Note: in case of ambiguity, the rule higher in the table wins.

Use string interpolation to concatenate short strings, as shown in the following code.

string displayName = $"{nameList[n].LastName}, {nameList[n].FirstName}";

To append strings in loops, especially when you are working with large amounts of text, use a StringBuilder object.

var phrase = "lalalalalalalalalalalalalalalalalalalalalalalalalalalalalala";
var manyPhrases = new StringBuilder();
for (var i = 0; i < 10000; i++)
{
    manyPhrases.Append(phrase);
}
//Console.WriteLine("tra" + manyPhrases);

Lambda Expression

  public Form2()
  {
      // You can use a lambda expression to define an event handler.
      this.Click += (s, e) =>
          {
              MessageBox.Show(
                  ((MouseEventArgs)e).Location.ToString());
          };
  }

Linq Queries

var localDistributors =
    from customer in customers
    join distributor in distributors on customer.City equals distributor.City
    select new { Customer = customer, Distributor = distributor };