C# - Static Keyword

Static Keyword in C#

The static keyword in C# is used to declare static members or static classes. Static members and classes belong to the type itself rather than an instance of the type. This means they are shared across all instances of the class (or exist without any instance).

Key Uses of static

1. Static Members (Fields, Properties, Methods, Events):

• A static member is shared by all instances of the class.
• It is accessed using the class name rather than an object

2.Static Classes:

• A static class can only contain static members.
• It cannot be instantiated.

3. Static Constructors:

A static constructor initializes static data or performs actions that only need to be performed once.

It is called automatically before any static member is accessed or an instance is created.

Static Properties

Static properties are used to encapsulate static fields with get and set logic.

public class AppConfig
{
    private static string _appName = "MyApplication";

    public static string AppName
    {
        get => _appName;
        set => _appName = value;
    }
}

Usage

Console.WriteLine(AppConfig.AppName);  // Output: MyApplication
AppConfig.AppName = "NewName";
Console.WriteLine(AppConfig.AppName);  // Output: NewName

2. Static Fields and Methods

public class Calculator
{
    public static int Add(int a, int b) => a + b;  // Static method
    public static int Counter = 0;                // Static field
}

Usage

int sum = Calculator.Add(5, 10);   // Call static method without creating an object
Console.WriteLine(sum);           // Output: 15

Calculator.Counter++;              // Access static field
Console.WriteLine(Calculator.Counter);  // Output: 1