using System;
using System.Linq;
using System.Data.Linq;
using System.Data.Linq.Mapping;

static class HelloLinqToSql {
    [Table(Name = "Contacts")]
    class Contact {
        [Column(IsPrimaryKey = true)]
        public int ContactID { get; set; }
        [Column(Name = "ContactName")]
        public string Name { get; set; }
        [Column]
        public string City { get; set; }
    }

    static void Main() {
        string path = System.IO.Path.GetFullPath("northwnd.mdf");
        DataContext db = new DataContext(path);

        var contacts =
          from contact in db.GetTable<Contact>()
          where contact.City == "Paris"
          select contact;

        foreach (var contact in contacts)
            Console.WriteLine("Bonjour " + contact.Name);
    }
}

    

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

public class MainClass{
   public static void Main(){
       int[] numbers = { 1, 3, 5, 4};
       var query = numbers.TakeWhile(( n, index) => n >= index);

       var query2 = numbers.SkipWhile(( n, index) => n >= index);
    }
}

    

   
 

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
    public static void Main() {
        string[] presidents = {"A", "Art", "Buch", "Bush", "Car", "land"};

        IEnumerable<string> items = presidents.Skip(1);

        foreach (string item in items)
            Console.WriteLine(item);
    }
}

    

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

public class MainClass{
public static void Main() {

            int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7};
            
            var allButFirst4Numbers = numbers.Skip(4);
            
            Console.WriteLine("All but first 4 numbers:");
            foreach (var n in allButFirst4Numbers) {
                Console.WriteLine(n);
            }
        }
}

    

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

public class MainClass {
public static void Main() {
List customers = GetCustomerList();

var waOrders =
from c in customers
from o in c.Orders
where c.Region == “R1”
select new { c.CustomerId, o.Id, o.OrderDate };

var allButFirst2Orders = waOrders.Skip(2);

Console.WriteLine(“All but first 2 orders in R1:”);
foreach (var order in allButFirst2Orders) {
Console.WriteLine(order);
}

}
static List GetCustomerList() {
List empTree = new List();
empTree.Add(new Product { ProductName = “A”, Category = “O”, UnitPrice = 12, UnitsInStock = 5, Total = 36, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = “B”, Category = “O”, UnitPrice = 2, UnitsInStock = 4, Total = 35, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = “C”, Category = “O”, UnitPrice = 112, UnitsInStock = 3, Total = 34, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = “D”, Category = “O”, UnitPrice = 112, UnitsInStock = 0, Total = 33, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = “E”, Category = “O”, UnitPrice = 1112, UnitsInStock = 2, Total = 32, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = “F”, Category = “O”, UnitPrice = 11112, UnitsInStock = 0, Total = 31, OrderDate = new DateTime(2005, 1, 1), Id = 1 });

List l = new List();
l.Add(new Customer { CompanyName = “A”, Region = “R1”, UnitsInStock = 1, Orders = empTree, CustomerId = 0 });
l.Add(new Customer { CompanyName = “B”, Region = “R2”, UnitsInStock = 2, Orders = empTree, CustomerId = 1 });
l.Add(new Customer { CompanyName = “C”, Region = “R3”, UnitsInStock = 3, Orders = empTree, CustomerId = 2 });
l.Add(new Customer { CompanyName = “D”, Region = “R4”, UnitsInStock = 4, Orders = empTree, CustomerId = 3 });
l.Add(new Customer { CompanyName = “E”, Region = “R5”, UnitsInStock = 5, Orders = empTree, CustomerId = 4 });
return l;
}
}
class Customer : IComparable {
public string CompanyName { get; set; }
public string Region { get; set; }
public List Orders { get; set; }
public int UnitsInStock { get; set; }
public int CustomerId { get; set; }

public override string ToString() {
return String.Format(“Id: {0}, Name: {1}, Region: {3}”, this.CustomerId, this.CompanyName, this.Region);
}
int IComparable.CompareTo(Customer other) {
if (other == null)
return 1;

if (this.CustomerId > other.CustomerId)
return 1;

if (this.CustomerId < other.CustomerId) return -1; return 0; } } class Product : IComparable {
public string ProductName { get; set; }
public string Category { get; set; }
public int UnitPrice { get; set; }
public int UnitsInStock { get; set; }
public int Total { get; set; }
public DateTime OrderDate { get; set; }
public int Id { get; set; }

public override string ToString() {
return String.Format(“Id: {0}, Name: {1} , Category: {3}”, this.Id, this.ProductName, this.Category);
}
int IComparable.CompareTo(Product other) {
if (other == null)
return 1;
if (this.Id > other.Id)
return 1;

if (this.Id < other.Id) return -1; return 0; } } [/csharp]

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

public class MainClass{
   public static void Main(){
       int[] numbers = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
       var query = numbers.Take(5);

       var query2 = numbers.Skip(5);
    }
}

    

   
 

using System;
using System.Collections.Generic;
using System.Linq;
public class MainClass {
    public static void Main() {

        int[] numbers = { 10, 9, 8, 7, 6 };
        IEnumerable<int> lastTwo = numbers.Skip(3);     // { 7, 6 }

    }
}