Linq101-Partitioning

using System;
using System.Linq;

namespace Linq101
{
    class Partitioning
    {
        /// <summary>
        /// This sample uses Take to get only the first 3 elements of the array.
        /// </summary>
        public void Linq20()
        {
            int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };

            var query = numbers.Take(3);

            Console.WriteLine("First 3 numbers:");
            foreach (var n in query)
            {
                Console.WriteLine(n);
            }
        }

        /// <summary>
        /// This sample uses Take to get the first 3 orders from customers in Washington.
        /// </summary>
        public void Linq21()
        {
            var customers = Data.GetCustomerList();

            var query = (from c in customers
                         from o in c.Orders
                         where c.Region == "WA"
                         select new { c.CustomerID, o.OrderID, o.OrderDate })
                .Take(3);

            //var query = (from c in customers
            //             where c.Region == "WA"
            //             from o in c.Orders
            //             select new { c.CustomerID, o.OrderID, o.OrderDate })
            //    .Take(3);

            Console.WriteLine("First 3 orders in WA:");
            foreach (var order in query)
            {
                ObjectDumper.Write(order);
            }
        }

        /// <summary>
        /// This sample uses Skip to get all but the first 4 elements of the array.
        /// </summary>
        public void Linq22()
        {
            int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };

            var query = numbers.Skip(4);

            Console.WriteLine("All but first 4 numbers:");
            foreach (var n in query)
            {
                Console.WriteLine(n);
            }
        }

        /// <summary>
        /// This sample uses Take to get all but the first 2 orders from customers in Washington.
        /// </summary>
        public void Linq23()
        {
            var customers = Data.GetCustomerList();

            var query = (from c in customers
                         where c.Region == "WA"
                         from o in c.Orders
                         select new { c.CustomerID, o.OrderID, o.OrderDate })
                .Skip(2);

            foreach (var order in query)
            {
                ObjectDumper.Write(order);
            }
        }

        /// <summary>
        /// This sample uses TakeWhile to return elements starting from the beginning of the array until a number is hit that is not less than 6.
        /// </summary>
        public void Linq24()
        {
            int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };

            var query = numbers.TakeWhile(n => n < 6);

            foreach (var n in query)
            {
                Console.WriteLine(n);
            }
        }

        /// <summary>
        /// This sample uses TakeWhile to return elements starting from the beginning of the array until a number is hit that is less than its position in the array.
        /// </summary>
        public void Linq25()
        {
            int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };

            var query = numbers.TakeWhile((number, index) => number > index);

            foreach (var n in query)
            {
                Console.WriteLine(n);
            }
        }

        /// <summary>
        /// This sample uses SkipWhile to get the elements of the array starting from the first element divisible by 3.
        /// </summary>
        public void Linq26()
        {
            int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };

            var query = numbers.SkipWhile(n => n % 3 != 0);

            foreach (var n in query)
            {
                Console.WriteLine(n);
            }
        }

        /// <summary>
        /// This sample uses SkipWhile to get the elements of the array starting from the first element less than its position.
        /// </summary>
        public void Linq27()
        {
            int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };

            var query = numbers.SkipWhile((number, index) => number > index);

            foreach (var n in query)
            {
                Console.WriteLine(n);
            }
        }
    }
}