C# Situation in which you should use static variable

In C#, static variables are used when you want a variable to be shared across all instances of a class. They are associated with the type itself rather than with specific instances of the type. Here's a situation where you might use a static variable in a C# class:

Example: Tracking the Number of Instances

Let's say you have a Car class, and you want to track the total number of Car instances created throughout the program's execution. You can achieve this using a static variable to keep count of the instances.

public class Car
{
    // Static variable to track the number of instances
    private static int numberOfCars = 0;

    public string Model { get; set; }

    public Car(string model)
    {
        Model = model;
        numberOfCars++; // Increment the count each time a new Car instance is created
    }

    public static int GetNumberOfCars()
    {
        return numberOfCars;
    }
}

class Program
{
    static void Main(string[] args)
    {
        Car car1 = new Car("Toyota");
        Car car2 = new Car("Honda");
        Car car3 = new Car("Ford");

        Console.WriteLine("Total number of cars: " + Car.GetNumberOfCars()); // Output: 3
    }
}

In this example, the numberOfCars variable is static, so it's shared among all instances of the Car class. Each time a new Car instance is created, the count is incremented, allowing you to keep track of the total number of Car instances throughout the program's execution.