soheil-moonesi

using System;
 // Define an abstract class called 'Shape' 
abstract class Shape { 
// An abstract method for calculating area, to be implemented by derived classes.
 public abstract double CalculateArea(); 
// A non-abstract method with a default implementation.
 public void DisplayArea() { 
       Console.WriteLine('Area: ' + CalculateArea()); }
 } 
// Create a derived class 'Circle' that inherits from 'Shape'

soheil-moonesi

 class Restaurants : IEnumerable
 {
        readonly public List<Restaurant> restaurants = new List<Restaurant> 
        {
            new Restaurant("Pizza", true),
            new Restaurant("Hamburger", false), 
            new Restaurant("Bread", true)
        };
        
        public GetEnumerator() => new OpenRestaurantsEnumerator(restaurants);

soheil-moonesi

class OpenRestaurantsEnumerator : IEnumerator
{
        private readonly List<Restaurant> _restaurants;
        private int _position = -1;

        public OpenRestaurantsEnumerator(List<Restaurant> restaurants)
        {
            _restaurants = restaurants;
        }

soheil-moonesi

    class Restaurants : IEnumerable
    {
        readonly public List<Restaurant> restaurants = new List<Restaurant> 
        {
            new Restaurant("Pizza", true),
            new Restaurant("Hamburger", false), 
            new Restaurant("Bread", true)
        };
        
        public IEnumerator GetEnumerator() => restaurants.GetEnumerator();

soheil-moonesi

// Without inheritance
public class SavingsAccount 
{
    private double balance;
    
    public double GetBalance() 
    {
        return this.balance;
    }
}

soheil-moonesi

namespace virgol
{
    class Program
    {
        static void Main()
        {
            UserMsg.sayGoodMorning();
        }
    }
}

soheil-moonesi

class Program
{
    static void Main()
    {
        MathHelperNonStatic mathHelper = new MathHelperNonStatic();
        int result =  mathHelper.Add(1, 2);
        Console.WriteLine(result);
    }

    public class MathHelperNonStatic

soheil-moonesi

class Program
{
    static void Main()
    {
        MathHelperExe();
    }

    public static class MathHelper
    {
        public static int Add(int a, int b)

soheil-moonesi

for(int i = 0; i < 50; i++)
{
   if(i % 7 == 0)
    {
        Console.WriteLine(i);
    }
}

soheil-moonesi

Console.WriteLine("soheil \t moonesi");
soheil   moonesi

Console.WriteLine("soheil \n moonesi");
soheil
 moonesi

Console.WriteLine("soheil \v moonesi");
soheil
 moonesi