Constructors

A constructor initializes an object when it is created.

Constructors.cs

using System;

class Rectangle
{
    public int Width;
    public int Height;

    public Rectangle(int width, int height)
    {
        Width = width;
        Height = height;
    }

    public int Area()
    {
        return Width * Height;
    }
}

class Program
{
    static void Main()
    {
        int width = ;
        Rectangle box = new Rectangle(width, 4);
        int area = box.Area();

        Console.WriteLine($"width={box.Width}");
        Console.WriteLine($"area={area}");
    }
}

using System;

class Rectangle
{
    public int Width;
    public int Height;

    public Rectangle(int width, int height)
    {
        Width = width;
        Height = height;
    }

    public int Area()
    {
        return Width * Height;
    }
}

class Program
{
    static void Main()
    {
        int width = ;
        Rectangle box = new Rectangle(width, 4);
        int area = box.Area();

        Console.WriteLine($"width={box.Width}");
        Console.WriteLine($"area={area}");
    }
}

using System;

class Rectangle
{
    public int Width;
    public int Height;

    public Rectangle(int width, int height)
    {
        Width = width;
        Height = height;
    }

    public int Area()
    {
        return Width * Height;
    }
}

class Program
{
    static void Main()
    {
        int width = ;
        Rectangle box = new Rectangle(width, 4);
        int area = box.Area();

        Console.WriteLine($"width={box.Width}");
        Console.WriteLine($"area={area}");
    }
}

constructor A constructor runs when `new` creates an object.