C# 6 new features

CSharp6NewFeatures

using System;
using System.Collections.Generic;
using System.Diagnostics;

using static System.Console;

namespace PlayingWithCSharp6
{
    class Program
    {
        static void Main(string[] args)
        {
            StringInterpolationEnhancements();
            UsingStaticClassesDemo();
            NullPropgationFeature(new Student { Name = "Adil" });
            DictionaryInitializer();
            Console.ReadLine();
        }


        public static void StringInterpolationEnhancements()
        {

            string name = "Adil";
            DateTime date = new DateTime(2015, 03, 13, 10, 15, 0);
            int versionYear = 2015;

            // Previously in C# 5
            WriteLine(string.Format("This code was written by {0} on {1} using Visual Studio {2}", name, date, versionYear));

            // In C# 6
            WriteLine(string.Format($"This code was written by {name} on {date} using Visual Studio {versionYear}"));

            // Infact you don't need to call string.format 
            WriteLine($"This code was written by {name} on {date} using Visual Studio {versionYear}");

            // This is especially handy when you add more parameters in string format over the time and the order get confusing
            string content = "blog";
            WriteLine(string.Format("This {3} was written by {0} on {1} using Visual Studio {2}", name, date, versionYear, content));

            WriteLine($"This {content} was written by {name} on {date} using Visual Studio {versionYear}");
        }

        public static void UsingStaticClassesDemo()
        {
            //Previously in C# 5
            Console.WriteLine("This is how to use static classes");

            // In C# 6 by adding namespace
            // using static System.Console;
            WriteLine("Just call the static method directly");
        }

        public static void NullPropgationFeature(Student student)
        {
            // Previously in C# 5
            if (student != null)
            {
                WriteLine(student.Name);
                if (student.Courses != null)
                {
                    foreach (var course in student.Courses)
                    {
                        WriteLine(course.Id);
                    }
                }
            }


            //In C# 6
            WriteLine(student?.Name);
            if (student.Courses != null)
            {
                foreach (var course in student.Courses)
                {
                    WriteLine(course.Id);
                }
            }

        }

        private static void DictionaryInitializer()
        {
            Dictionary<string, int> dictionary = new Dictionary<string, int> {["Year"] = 2015,["Month"] = 03,["Day"] = 15 };
        }

        public class OtherEnhancements
        {
            // A getter only property with readyonly backing field
            public int DemoInt { get; }

            // An auto property intialized with default value
            public string DemoString { get; set; } = "Demo";

            public OtherEnhancements()
            {
                // Assignment in constructor for getter only field behaves like readonly field
                this.DemoInt = 100;
            }

            public void DemoMethod()
            {
                try
                {

                }
                // catch exception with filters
                catch (System.IO.FileNotFoundException exception) when (exception.FileName == "abc.txt")
                {
                    // handle only for particular file 
                    // In previous version of C#, you have to check it inside
                    // and then re throw which would result in losing exception data
                }
            }

            //Expression-bodied members
            public override string ToString() => $"Value : {DemoInt}";
        }

        public class Student
        {
            public string Name { get; set; }

            public IList<Course> Courses { get; set; }
        }

        public class Course
        {
            public int Id { get; set; }
        }
    }
}