//.NET 6 includes C# 10, which comes with many new enhancements

​

using System;

​

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {   

        //DateOnly and TimeOnly is what happens when you split DateTime with a saw down the middle

        TestDateOnlyAndTimeOnly();

        //Pass default value in FirstOrDefault or other OrDefault LINQ operations

        TestLinqOrDefault();

        //Iterate enumarable in chunks

        TestIEnumerableChunk();

        //Assign priority to items in queue and always pop the highest

        TestPriorityQueue();

        //MaxBy returns whole object with max property

        TestMaxBy();

        //Consts now allow string interpolation

        TestConstInterpolation();

    }

    public static void TestDateOnlyAndTimeOnly()

    {

        WriteHeading("Date Only and Time Only", "No more DateTime shinnanigans when you only need Date or Time.");

        DateOnly date = DateOnly.MinValue;

        Console.WriteLine("DateOnly.MinValue: "  + date); 

        TimeOnly time = TimeOnly.MinValue;

        Console.WriteLine("TimeOnly.MinValue: " + time);

        TimeOnly startTime = TimeOnly.Parse("10:00am");

        TimeOnly endTime = TimeOnly.Parse("10:00pm");

        Console.WriteLine();

        var isBetween = TimeOnly.Parse("9:00am").IsBetween(startTime, endTime);

        Console.WriteLine("Time 9:00am is between: 10:00am and 10:00pm: " + isBetween);

        isBetween = TimeOnly.Parse("1:30pm").IsBetween(startTime, endTime);

        Console.WriteLine("Time 1:30am is between: 10:00am and 10:00pm: " + isBetween);

    }

    public static void TestLinqOrDefault()

    {

        WriteHeading("LINQ OrDefault Enhancement", "Pass Default value for FirstOrDefault and other OrDefault calls.");

        var list = new List<int?> { 1, 2, 3 };

​

        var result = list.FirstOrDefault(x => x == 4, -1);

        Console.WriteLine("FirstOrDefault for 4 returned: " + result);

    }

    public static void TestIEnumerableChunk()

    {

        WriteHeading("IEnumerable Chunk", "Easily iterate chunks of enumerable.");

        var list = Enumerable.Range(1, 95);

        var chunkSize = 10;

        var chunkIndex = 0;

        foreach(var chunk in list.Chunk(chunkSize))  

        {

            Console.Write("Chunk #" + chunkIndex + ": ");

            foreach(var item in chunk)

            {

                Console.Write(item + " ");

            }

            Console.WriteLine();

            chunkIndex++;

        }

    }

    public static void TestPriorityQueue()

    {

        WriteHeading("Priority Queue", "Item with highest priority is the first one that gets popped.");

​

        var pQueue = new PriorityQueue<string, int>();

        pQueue.Enqueue("A", 50);

        pQueue.Enqueue("B", 6);

        pQueue.Enqueue("C", 23);

        while (pQueue.TryDequeue(out string item, out int priority))

        {

            Console.WriteLine($"Popped: {item}. Priority: {priority}");

        }

    }

    class Customer

    {

        public string Name { get; set; }

        public int Age { get; set; }

    }

​

    public static void TestMaxBy()

    {

        WriteHeading("MaxBy MinBy", "Return whole object that contains max/min property value instead of just max/min value.");

​

        var customers = new List<Customer>

        {

            new Customer

            {

                Name = "John Doe", 

                Age = 35

            }, 

            new Customer

            {

                Name = "Jane Doe", 

                Age = 31

            }

        };

        Console.WriteLine("Max Age:" + customers.Max(x => x.Age));

        Console.WriteLine("MaxBy Age:");

        FiddleHelper.Dump(customers.MaxBy(x => x.Age));

        Console.WriteLine("");

        Console.WriteLine("Min Age:" + customers.Min(x => x.Age));

        Console.WriteLine("MinBy Age:");

        FiddleHelper.Dump(customers.MinBy(x => x.Age));

    }

    private const string scheme = "https";

    private const string url = $"{scheme}://dotnetfidlle.net";

    public static void TestConstInterpolation()

    {

        WriteHeading("Const String Inerpolation", "Use $\"{...}...\" in string constants");

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        Console.WriteLine("Url: " + url);

    }

​

    public static void WriteHeading(string name, string description = null)

    {

        Console.WriteLine();

        Console.WriteLine();

        Console.WriteLine("===========================");

        Console.WriteLine(name);

        Console.WriteLine("-  " + description);

        Console.WriteLine();

        Console.WriteLine();

    }

}