C# Online Compiler | .NET Fiddle

<no name> by Anonymous

/*
using System;
using System.Collections.Generic;
using System.Linq;
					
public class Program
{
	public static void Main()
	{
		List<string> names = new List<string>() {"Monika", "Karol"};
		char firstLetter = 'K';
		var results = from e in names where e[0] == firstLetter
		select e;
		firstLetter = 'M';
		List<string> resultList = results.ToList();
		names.Add("Marta");
		var finalResults = from e in resultList where e[0] == firstLetter

		select e;

		foreach (string s in finalResults) Console.Write(s+" ");

		// Output: Monika
	}
}
*/
/////////////////////////////////////////////////////////////////////////

/*
using System;
                                       
public class Program
{
        public void DoSomething(params int[] x) {
                        int max = x[0];
                        for (int i = 0; i < x.Length; i++)
                        if (x[i] > max) max = x[i];
                        Console.WriteLine(max);
                }
        public void Main()
        {
                Console.WriteLine("dupa");
                DoSomething(1,2,3);
                //DoSomething({1,2,3});  // COMPILE ERROR
                //DoSomething(new int{1,2,3}); // COMPILE ERROR
                DoSomething(new int[]{1,2,3});
        }
}

*/

/////////////////////////////////////////////////////////////////////
/*
using System;
using System.Collections;
			
public class BoxInt : IComparable<int>
{
	public int Value {get;private set;}
	public BoxInt(int value){Value=value;}
	public int CompareTo(int other)
	{
		return this.Value.CompareTo(other);
	}
	int IComparable<int>.CompareTo(int other)
	{
		return other.CompareTo(this.Value);
	}
}

public class Program
{
	public static void Main()
	{
		Console.WriteLine("dziala");
		BoxInt a = new BoxInt(1);
		IComparable<int> b = new BoxInt(1);
		Console.WriteLine("{0},{1}", a.CompareTo(2), b.CompareTo(2));
		// Output: -1, 1
	}
}
*/

/*
using System;
					
class A {public virtual void m(){Console.Write("A");}}
class B:A {public override void m(){Console.Write("B");}}
class C:B {new public virtual void m(){Console.Write("C");}}
class D:C {public override void m(){Console.Write("D");}}

public class Program
{
	public void Main()
	{
		Console.WriteLine("dziala");
		D d = new D();
		A a = d; 
		a.m();
		B b = d;
		b.m();
		
		// Output: BB
	}
}

*/

/*
using System;
					
public class Program
{
	struct Point{
			public int x,y;
			public Point(int x, int y){this.x=x; this.y=y;}
		}
	
	public static void Main()
	{
		Console.WriteLine("dziala");
		Point A = new Point(1,1);
		Point B = A;
		B.x=2;
		//Console.WriteLine("{0},{1}", B.x, A.x);
		B.y=A.x*2;
		A.y=A.y*2;
		Console.WriteLine("{0},{1}", A.x, A.y);
		
		// Output: 1, 2
	}
}

*/

/// Rownolegly lepszy
/*

using System;
using System.Threading.Tasks;

public class Program
{
	public static void Main()
	{
		Parallel.Invoke( 
			() => Console.WriteLine("Action 1"), 
			() => Console.WriteLine("Action 2"), 
			() => Console.WriteLine("Action 3" ) 
		);
	}
}

*/


//// Rownolegly
/*
using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;

public class Program
{
	public static void Main()
	{
		List<string> names = new List<string>() {"Kasia", "Anna", "Ola"};
		Parallel.ForEach(names, (name) => {Console.WriteLine("{0}", name); } );
	}
}

*/



///// DELEGATE
/*
using System;

public delegate int BinaryOp(int x, int y);

public class Program
{
	public static int Add(int x, int y) {
		return x + y;
	}
	public static void Main() {
		BinaryOp op;
		op = new BinaryOp(Add);
		op = Add; //Implicit delegate construction
		int result = op(5, 5); //op.Invoke(5, 5);
		Console.WriteLine("{0}", result);
	}	
}

*/



using System;
using System.Collections.Generic;
using System.Linq;

namespace LinqTest.Test
{

    public class Employee
    {
        public int EmpId { get; set; }
        public string Name { get; set; }
        public DateTime? DOB { get; set; }
        public decimal Salary { get; set; }
        public DateTime DOJ { get; set; }
        public bool IsActive { get; set; }
    }


    public class Book
    {
        public int BookId { get; set; }
        public string Title { get; set; }
        public double Price { get; set; }
    }

    public class BookOrder
    {
        public int OrderId { get; set; }
        public int EmpId { get; set; }
        public int BookId { get; set; }
        public int Quantity { get; set; }
    }


    public class Linqtest
    {
        List<Employee> Employees;
        List<Book> Books;
        List<BookOrder> Orders;

        public void InitializeData()
        {
            Employees = new List<Employee>();
            Books = new List<Book>();
            Orders = new List<BookOrder>();

            Employees.Add(new Employee(){EmpId = 1, Name ="Test1" ,  DOB = new DateTime(1980,12,15),IsActive = true,Salary = 4500});
            Employees.Add(new Employee() { EmpId = 11, Name = "Test2", DOB = new DateTime(1981, 12, 15), IsActive = true, Salary = 3500 });
            Employees.Add(new Employee() { EmpId = 5, Name = "Test3", DOB = new DateTime(1970, 2, 15), IsActive = true, Salary = 5500 });
            Employees.Add(new Employee() { EmpId = 8, Name = "Test4", DOB = new DateTime(1978, 1, 15), IsActive = true, Salary = 7500 });
            Employees.Add(new Employee() { EmpId = 9, Name = "Test5", DOB = new DateTime(1972, 2, 5), IsActive = true, Salary = 2500 });
            Employees.Add(new Employee() { EmpId = 10, Name = "Test6", DOB = new DateTime(1980, 10, 8), IsActive = false, Salary = 5500 });
            Employees.Add(new Employee() { EmpId = 15, Name = "Test7", DOB = new DateTime(1983, 11, 25), IsActive = true, Salary = 3500 });

            Books.Add(new Book(){BookId = 2, Price = 24.99,Title = "British Food"});
            Books.Add(new Book() { BookId = 5, Price = 4.99, Title = "Holidays in UK" });
            Books.Add(new Book() { BookId = 7, Price = 7.99, Title = "UK Laws" });


            Orders.Add(new BookOrder(){EmpId = 1,OrderId = 1,BookId = 2,Quantity = 3});
            Orders.Add(new BookOrder() { EmpId = 1, OrderId = 1, BookId = 5, Quantity = 1 });
            Orders.Add(new BookOrder() { EmpId = 1, OrderId = 2, BookId = 7, Quantity = 5 });
            Orders.Add(new BookOrder() { EmpId = 11, OrderId = 3, BookId = 2, Quantity = 3 });
            Orders.Add(new BookOrder() { EmpId = 11, OrderId = 4, BookId = 7, Quantity = 3 });
        }


        public void CheckEmpCount()
        {

            var res = Employees
                .Where(e => e.EmpId > 5)
                .Where(t =>t.Salary>=5000);


            res = Employees
                .Where(e => e.EmpId > 5);


        }

        public void TestGroupBy()
        {
            var res = from e in Employees
                group e by e.Salary;


            var res1 = Employees.GroupBy(e => e.Salary);
        }

        public void TestJoin()
        {
            var res = from o in Orders
                join Employee e in Employees
                    on o.EmpId equals e.EmpId
                where o.EmpId == 11
                select o;

        }

        public void TestJoinData()
        {
            var res = from o in Orders
                join Employee e in Employees
                    on o.EmpId equals e.EmpId 
                join Book b in Books
                    on o.BookId equals b.BookId 
                orderby e.EmpId
                select new {o.OrderId, e.Name, b.Title, b.Price};
			
			

        }
		
		public void MyTest()
        {
            var results = from o in Orders
                join Employee e in Employees
                    on o.EmpId equals e.EmpId 
                join Book b in Books
                    on o.BookId equals b.BookId 
                orderby e.EmpId
                select new {o.OrderId, e.Name, b.Title, b.Price};
			

			foreach (var czytelnik in results) {
				Console.WriteLine("Imie: {0}, Nazwisko: {1}",
								  czytelnik.Name, czytelnik.Title);
				
			}
		
		}
		
		public void MyTest2()
        {
            var results = from o in Orders
                join Employee e in Employees
                    on o.EmpId equals e.EmpId 
                join Book b in Books
                    on o.BookId equals b.BookId 
				group o by new {e.EmpId} into g
				orderby g.Key.EmpId
                select g;
			

			foreach (var group in results) {
				Console.WriteLine("Imie: {0}",
								  group.Key.EmpId);
				foreach (var value in group) {
					Console.WriteLine("{0}",
								  value);
				}
				
			}
		
		}
		
		public void MyTest4()
        {
            var results = from e in Employees
                join BookOrder o in Orders
                    on e.EmpId equals o.EmpId 
                join Book b in Books
                    on o.BookId equals b.BookId into wyp_bks
				group wyp_bks by new {e.EmpId, e.Name} into g
				orderby g.Key.EmpId
                select g;
			

			foreach (var group in results) {
				Console.WriteLine("Imie: {0}",
								  group.Key.Name);
				foreach (var value in group) {
					Console.WriteLine("{0}",
								  value.Single().Title);
				}
				
			}

		
		
		}
		
		/*public void MyTest3()  //Mockup
        {
			List<Czytelnik> czytelnicy = getCzytelnicy();
			List<Ksiazka> ksiazki = getKsiazki();
			List<Wypozyczenie> wypozyczenia = getWypozyczenia();
			
            var results = from wyp in wypozyczenia
                join Czytelnik czyt in czytelnicy
                    on czyt.ID equals wyp.czytelnikID
                join Ksiazka k in ksiazki
                    on wyp.ksiazkaID equals k.ID
                orderby czyt.imie, czyt.nazwisko
                select new {czyt.imie, czyt.nazwisko, k.tytul, k.ID};
			

			foreach (var czytelnik in results) {
				Console.WriteLine("Imie: {0}, Nazwisko: {1}, Tytul: {2}",
								  czytelnik.Name, czytelnik.Title);
			}
		
		}*/
		

    }
	
	public class Program
	{

		public static void Main() {
			Linqtest test = new Linqtest();
			test.InitializeData();
			test.TestJoinData();
			test.MyTest4();
		}	
	}
}

​x
 
/*
using System;
using System.Collections.Generic;
using System.Linq;
                    
public class Program
{
    public static void Main()
    {
        List<string> names = new List<string>() {"Monika", "Karol"};
        char firstLetter = 'K';
        var results = from e in names where e[0] == firstLetter
        select e;
        firstLetter = 'M';
        List<string> resultList = results.ToList();
        names.Add("Marta");
        var finalResults = from e in resultList where e[0] == firstLetter
​
        select e;
​
        foreach (string s in finalResults) Console.Write(s+" ");
​
        // Output: Monika
    }
}
*/
/////////////////////////////////////////////////////////////////////////
​
/*
using System;
                                       
public class Program
{
        public void DoSomething(params int[] x) {
                        int max = x[0];
                        for (int i = 0; i < x.Length; i++)
                        if (x[i] > max) max = x[i];
                        Console.WriteLine(max);
                }
        public void Main()
        {
                Console.WriteLine("dupa");
                DoSomething(1,2,3);
                //DoSomething({1,2,3});  // COMPILE ERROR
                //DoSomething(new int{1,2,3}); // COMPILE ERROR
                DoSomething(new int[]{1,2,3});
        }
}
​
*/
​
/////////////////////////////////////////////////////////////////////
/*
using System;
using System.Collections;
            
public class BoxInt : IComparable<int>
{
    public int Value {get;private set;}
    public BoxInt(int value){Value=value;}
    public int CompareTo(int other)
    {
        return this.Value.CompareTo(other);
    }
    int IComparable<int>.CompareTo(int other)
    {
        return other.CompareTo(this.Value);
    }
}
​
public class Program
{
    public static void Main()
    {
        Console.WriteLine("dziala");
        BoxInt a = new BoxInt(1);
        IComparable<int> b = new BoxInt(1);
        Console.WriteLine("{0},{1}", a.CompareTo(2), b.CompareTo(2));
        // Output: -1, 1
    }
}
*/
​
/*
using System;
                    
class A {public virtual void m(){Console.Write("A");}}
class B:A {public override void m(){Console.Write("B");}}
class C:B {new public virtual void m(){Console.Write("C");}}
class D:C {public override void m(){Console.Write("D");}}
​
public class Program
{
    public void Main()
    {
        Console.WriteLine("dziala");
        D d = new D();
        A a = d; 
        a.m();
        B b = d;
        b.m();
        
        // Output: BB
    }
}
​
*/
​
/*
using System;
                    
public class Program
{
    struct Point{
            public int x,y;
            public Point(int x, int y){this.x=x; this.y=y;}
        }
    
    public static void Main()
    {
        Console.WriteLine("dziala");
        Point A = new Point(1,1);
        Point B = A;
        B.x=2;
        //Console.WriteLine("{0},{1}", B.x, A.x);
        B.y=A.x*2;
        A.y=A.y*2;
        Console.WriteLine("{0},{1}", A.x, A.y);
        
        // Output: 1, 2
    }
}
​
*/
​
/// Rownolegly lepszy
/*
​
using System;
using System.Threading.Tasks;
​
public class Program
{
    public static void Main()
    {
        Parallel.Invoke( 
            () => Console.WriteLine("Action 1"), 
            () => Console.WriteLine("Action 2"), 
            () => Console.WriteLine("Action 3" ) 
        );
    }
}
​
*/
​
​
//// Rownolegly
/*
using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
​
public class Program
{
    public static void Main()
    {
        List<string> names = new List<string>() {"Kasia", "Anna", "Ola"};
        Parallel.ForEach(names, (name) => {Console.WriteLine("{0}", name); } );
    }
}
​
*/
​
​
​
///// DELEGATE
/*
using System;
​
public delegate int BinaryOp(int x, int y);
​
public class Program
{
    public static int Add(int x, int y) {
        return x + y;
    }
    public static void Main() {
        BinaryOp op;
        op = new BinaryOp(Add);
        op = Add; //Implicit delegate construction
        int result = op(5, 5); //op.Invoke(5, 5);
        Console.WriteLine("{0}", result);
    }   
}
​
*/
​
​
​
using System;
using System.Collections.Generic;
using System.Linq;
​
namespace LinqTest.Test
{
​
    public class Employee
    {
        public int EmpId { get; set; }
        public string Name { get; set; }
        public DateTime? DOB { get; set; }
        public decimal Salary { get; set; }
        public DateTime DOJ { get; set; }
        public bool IsActive { get; set; }
    }
​
​
    public class Book
    {
        public int BookId { get; set; }
        public string Title { get; set; }
        public double Price { get; set; }
    }
​
    public class BookOrder
    {
        public int OrderId { get; set; }
        public int EmpId { get; set; }
        public int BookId { get; set; }
        public int Quantity { get; set; }
    }
​
​
    public class Linqtest
    {
        List<Employee> Employees;
        List<Book> Books;
        List<BookOrder> Orders;
​
        public void InitializeData()
        {
            Employees = new List<Employee>();
            Books = new List<Book>();
            Orders = new List<BookOrder>();
​
            Employees.Add(new Employee(){EmpId = 1, Name ="Test1" ,  DOB = new DateTime(1980,12,15),IsActive = true,Salary = 4500});
            Employees.Add(new Employee() { EmpId = 11, Name = "Test2", DOB = new DateTime(1981, 12, 15), IsActive = true, Salary = 3500 });
            Employees.Add(new Employee() { EmpId = 5, Name = "Test3", DOB = new DateTime(1970, 2, 15), IsActive = true, Salary = 5500 });
            Employees.Add(new Employee() { EmpId = 8, Name = "Test4", DOB = new DateTime(1978, 1, 15), IsActive = true, Salary = 7500 });
            Employees.Add(new Employee() { EmpId = 9, Name = "Test5", DOB = new DateTime(1972, 2, 5), IsActive = true, Salary = 2500 });
            Employees.Add(new Employee() { EmpId = 10, Name = "Test6", DOB = new DateTime(1980, 10, 8), IsActive = false, Salary = 5500 });
            Employees.Add(new Employee() { EmpId = 15, Name = "Test7", DOB = new DateTime(1983, 11, 25), IsActive = true, Salary = 3500 });
​
            Books.Add(new Book(){BookId = 2, Price = 24.99,Title = "British Food"});
            Books.Add(new Book() { BookId = 5, Price = 4.99, Title = "Holidays in UK" });
            Books.Add(new Book() { BookId = 7, Price = 7.99, Title = "UK Laws" });
​
​
            Orders.Add(new BookOrder(){EmpId = 1,OrderId = 1,BookId = 2,Quantity = 3});
            Orders.Add(new BookOrder() { EmpId = 1, OrderId = 1, BookId = 5, Quantity = 1 });
            Orders.Add(new BookOrder() { EmpId = 1, OrderId = 2, BookId = 7, Quantity = 5 });
            Orders.Add(new BookOrder() { EmpId = 11, OrderId = 3, BookId = 2, Quantity = 3 });
            Orders.Add(new BookOrder() { EmpId = 11, OrderId = 4, BookId = 7, Quantity = 3 });
        }
​
​
        public void CheckEmpCount()
        {
​
            var res = Employees
                .Where(e => e.EmpId > 5)
                .Where(t =>t.Salary>=5000);
​
​
            res = Employees
                .Where(e => e.EmpId > 5);
​
​
        }
​
        public void TestGroupBy()
        {
            var res = from e in Employees
                group e by e.Salary;
​
​
            var res1 = Employees.GroupBy(e => e.Salary);
        }
​
        public void TestJoin()
        {
            var res = from o in Orders
                join Employee e in Employees
                    on o.EmpId equals e.EmpId
                where o.EmpId == 11
                select o;
​
        }
​
        public void TestJoinData()
        {
            var res = from o in Orders
                join Employee e in Employees
                    on o.EmpId equals e.EmpId 
                join Book b in Books
                    on o.BookId equals b.BookId 
                orderby e.EmpId
                select new {o.OrderId, e.Name, b.Title, b.Price};
            
            
​
        }
        
        public void MyTest()
        {
            var results = from o in Orders
                join Employee e in Employees
                    on o.EmpId equals e.EmpId 
                join Book b in Books
                    on o.BookId equals b.BookId 
                orderby e.EmpId
                select new {o.OrderId, e.Name, b.Title, b.Price};
            
​
            foreach (var czytelnik in results) {
                Console.WriteLine("Imie: {0}, Nazwisko: {1}",
                                  czytelnik.Name, czytelnik.Title);
                
            }
        
        }
        
        public void MyTest2()
        {
            var results = from o in Orders
                join Employee e in Employees
                    on o.EmpId equals e.EmpId 
                join Book b in Books
                    on o.BookId equals b.BookId 
                group o by new {e.EmpId} into g
                orderby g.Key.EmpId
                select g;
            
​
            foreach (var group in results) {
                Console.WriteLine("Imie: {0}",
                                  group.Key.EmpId);
                foreach (var value in group) {
                    Console.WriteLine("{0}",
                                  value);
                }
                
            }
        
        }
        
        public void MyTest4()
        {
            var results = from e in Employees
                join BookOrder o in Orders
                    on e.EmpId equals o.EmpId 
                join Book b in Books
                    on o.BookId equals b.BookId into wyp_bks
                group wyp_bks by new {e.EmpId, e.Name} into g
                orderby g.Key.EmpId
                select g;
            
​
            foreach (var group in results) {
                Console.WriteLine("Imie: {0}",
                                  group.Key.Name);
                foreach (var value in group) {
                    Console.WriteLine("{0}",
                                  value.Single().Title);
                }
                
            }
​
        
        
        }
        
        /*public void MyTest3()  //Mockup
        {
            List<Czytelnik> czytelnicy = getCzytelnicy();
            List<Ksiazka> ksiazki = getKsiazki();
            List<Wypozyczenie> wypozyczenia = getWypozyczenia();
            
            var results = from wyp in wypozyczenia
                join Czytelnik czyt in czytelnicy
                    on czyt.ID equals wyp.czytelnikID
                join Ksiazka k in ksiazki
                    on wyp.ksiazkaID equals k.ID
                orderby czyt.imie, czyt.nazwisko
                select new {czyt.imie, czyt.nazwisko, k.tytul, k.ID};
            
​
            foreach (var czytelnik in results) {
                Console.WriteLine("Imie: {0}, Nazwisko: {1}, Tytul: {2}",
                                  czytelnik.Name, czytelnik.Title);
            }
        
        }*/
        
​
    }
    
    public class Program
    {
​
        public static void Main() {
            Linqtest test = new Linqtest();
            test.InitializeData();
            test.TestJoinData();
            test.MyTest4();
        }   
    }
}
​
​
​
​
​

My Address Book is
A - Add New Address
D - Delate Address
M - Modify Address
V - View Addresses
Q - Quit

Choice (A,D,M,V, or Q)

Cached Result
Last Run:	12:12:23 pm
Compile:	0.108s
Execute:	0s
Memory:	32kb
CPU:	0s

View IL Code