C＃编码标准和命名约定

Below are our C# coding standards, naming conventions, and best practices.
Use these in your own projects and/or adjust these to your own needs.

douse PascalCasing for class names and method names.

public class ClientActivity{    
  public void ClearStatistics()   
  {        //...   
}    
  public void CalculateStatistics()    {        //...   
  }
}

Why: consistent with the Microsoft's .NET Framework and easy to read.

douse camelCasing for local variables and method arguments.

public class UserLog
{   
  public void Add(LogEvent logEvent)  
  {      
  int itemCount = logEvent.Items.Count;      
    // ...    
                                                              
  }
}

Why: consistent with the Microsoft's .NET Framework and easy to read.

do notuse Hungarian notation or any other type identification in identifiers

// Correct
int counter;
string name; 
// Avoid
int iCounter;
string strName;

Why: consistent with the Microsoft's .NET Framework and Visual Studio IDE makes determining types very easy (via tooltips). In general you want to avoid type indicators in any identifier.

do notuse Screaming Caps for constants or readonly variables

    // Correct
    public static const string ShippingType = "DropShip";
     
    // Avoid
    public static const string SHIPPINGTYPE = "DropShip";

Why: consistent with the Microsoft's .NET Framework. Caps grap too much attention.

avoidusing Abbreviations. Exceptions: abbreviations commonly used as names, such as Id, Xml, Ftp, Uri

    // Correct
    UserGroup userGroup;
    Assignment employeeAssignment;
     
    // Avoid
    UserGroup usrGrp;
    Assignment empAssignment;
     
    // Exceptions
    CustomerId customerId;
    XmlDocument xmlDocument;
    FtpHelper ftpHelper;
    UriPart uriPart;

Why: consistent with the Microsoft's .NET Framework and prevents inconsistent abbreviations.

douse PascalCasing for abbreviations 3 characters or more (2 chars are both uppercase)

    htmlHelper htmlHelper;
    FtpTransfer ftpTransfer;
    UIControl uiControl;

Why: consistent with the Microsoft's .NET Framework. Caps would grap visually too much attention.

do notuse Underscores in identifiers. Exception: you can prefix private static variables
with an underscore.

    // Correct
    public DateTime clientAppointment;
    public TimeSpan timeLeft;
     
    // Avoid
    public DateTime client_Appointment;
    public TimeSpan time_Left;
     
    // Exception
    private DateTime _registrationDate;

Why: consistent with the Microsoft's .NET Framework and makes code more natural to read (without 'slur'). Also avoids underline stress (inability to see underline).

douse predefined type names instead of system type names like Int16, Single, UInt64, etc

    // Correct
    string firstName;
    int lastIndex;
    bool isSaved;
     
    // Avoid
    String firstName;
    Int32 lastIndex;
    Boolean isSaved;

Why: consistent with the Microsoft's .NET Framework and makes code more natural to read.

douse implicit type var for local variable declarations. Exception: primitive types (int, string,
double, etc) use predefined names.

    var stream = File.Create(path);
    var customers = new Dictionary();
     
    // Exceptions
    int index = 100;
    string timeSheet;
    bool isCompleted;

Why: removes clutter, particularly with complex generic types. Type is easily detected with Visual Studio tooltips.

douse noun or noun phrases to name a class.

    public class Employee
    {
    }
    public class BusinessLocation
    {
    }
    public class DocumentCollection
    {
    }

Why: consistent with the Microsoft's .NET Framework and easy to remember.

doprefix interfaces with the letter I. Interface names are noun (phrases) or adjectives.

    public interface IShape
    {
    }
    public interface IShapeCollection
    {
    }
    public interface IGroupable
    {
    }

Why: consistent with the Microsoft's .NET Framework.

doname source files according to their main classes. Exception: file names with partial classes
reflect their source or purpose, e.g. designer, generated, etc.

    // Located in Task.cs
    public partial class Task
    {
        //...
    }

    // Located in Task.generated.cs
    public partial class Task
    {
        //...
    }

Why: consistent with the Microsoft practices. Files are alphabetically sorted and partial classes remain adjacent.

doorganize namespaces with a clearly defined structure

    // Examples
    namespace Company.Product.Module.SubModule
    namespace Product.Module.Component
    namespace Product.Layer.Module.Group

Why: consistent with the Microsoft's .NET Framework. Maintains good organization of your code base.

dovertically align curly brackets.

    // Correct
    class Program
    {
        static void Main(string[] args)
        {
        }
    }

Why: Microsoft has a different standard, but developers have overwhelmingly preferred vertically aligned brackets.

dodeclare all member variables at the top of a class, with static variables at the very top.

    // Correct
    public class Account
    {
        public static string BankName;
        public static decimal Reserves;
     
        public string Number {get; set;}
        public DateTime DateOpened {get; set;}
        public DateTime DateClosed {get; set;}
        public decimal Balance {get; set;}
     
        // Constructor
        public Account()
        {
            // ...
        }
    }

Why: generally accepted practice that prevents the need to hunt for variable declarations.

douse 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
    }

Why: consistent with the Microsoft's .NET Framework and makes the code more natural to read. Plural flags because enum can hold multiple values (using bitwise 'OR').

do notexplicitly specify a type of an enum or values of enums (except bit fields)

    // Don't
    public enum Direction : long
    {
        North = 1,
        East = 2,
        South = 3,
        West = 4
    }
     
    // Correct
    public enum Direction
    {
        North,
        East,
        South,
        West
    }

Why: can create confusion when relying on actual types and values.

do notsuffix enum names with Enum

    // Don't
    public enum CoinEnum
    {
        Penny,
        Nickel,
        Dime,
        Quarter,
        Dollar
    }
     
    // Correct
    public enum Coin
    {
        Penny,
        Nickel,
        Dime,
        Quarter,
        Dollar
    }

Why: consistent with the Microsoft's .NET Framework and consistent with prior rule of no type indicators in identifiers.