C# Coding Standards/Conventions And Best Practices

 

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

• Class and Method names should always be in Pascal Case [ The first character of all words is in upper case and other characters are in lower case. Example: HelloWorld ]

• 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
  public DateTime fromDate;
  public String firstName;
   
  
  // Avoid
  public DateTime from_Date;
  public String first_Name;

• Avoid the use of System data types and prefer using the Predefined data types.
  // Correct
  int employeeId;
  string employeeName;
  bool isActive;
   
  
  // Avoid
  Int32 employeeId;
  String employeeName;
  Boolean isActive;

• Always prefix an interface with letter I.

• 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);
  //--------------------------
   
  
  // Avoid
  String firstName = "Shubham";
  //--------------------------
  //--------------------------
  //--------------------------
  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; }

• 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 // or /// for comments avoid using /* … *

• Dont have number of classes in single file. Create a separate file for each class.

• Avoid the use of var in place of dynamic.

• Do not hardcode string or numbers; 
  instead, create separate file sfor constants and put all constants into that or declare constants on top of file 
  and refer these constants into your code.

• Use String.Empty instead of “”

• While working with the collection be aware of the below points:

1. While returning collection return empty collection instead of returning null when you have no data to return.
2. Always check Any() operator instead of checking count i.e. collection.Count > 0 and checking of null
3. Use foreach instead of for loop while traversing.
4. Use IList<T>, IEnumrable<T>,ICollection<T> instead of concrete classes e.g. using List<>

Architecture Design Level Guidelines

• Do not access the database from UI pages. Use the data access layer to perform all tasks which are related to the database.
• Try to use design patterns, practices, and SOLID principles.
• Always refer to minified versions of javascript or CSS files, this will reduce unnecessary overhead to the server
• Use Nullable Data Types Whenever Required
  
  int index = 0; // simple declaration of int
  int? index = null; // nullable data type declaration
  
  

Prefer “is” and “as” Operators While Casting

• Use Conditional Attributes When You Need Them