HR Management system part 2

click here to download source code

Group By and ToLookup in Linq C#

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;



namespace ConsoleApplication1

{

    class student

    {

        public int studentID { get; set; }

        public string studentName { get; set; }

        public int Age { get; set; }

    }

    class Program

    {

        static void Main(string[] args)

        {

            List<student> li = new List<student>()

          {



             new student() { studentID = 5, studentName = "Ron" , Age = 21 },

            new student() { studentID = 6, studentName = "Chris",  Age = 18 },

             new student() { studentID = 7, studentName = "Rob",Age = 19  },

            new student() { studentID = 8, studentName = "Rob",Age = 21  },

            new student() { studentID = 1, studentName = "John", Age = 18 },

            new student() { studentID = 2, studentName = "Steve",  Age = 21 },

            new student() { studentID = 3, studentName = "Bill",  Age = 25 },

            new student() { studentID = 4, studentName = "Ram" , Age = 19 },

            new student() { studentID = 9, studentName = "Bill",Age = 19  },



        };



           // var agegroup = li.GroupBy(x => x.Age).ToList();

            var agegroup = li.ToLookup(x => x.Age).ToList();

            foreach (var group in agegroup)

            {

                Console.ForegroundColor = System.ConsoleColor.Green;



                Console.WriteLine("====AGE:"+group.Key+"====");

                Console.ForegroundColor = System.ConsoleColor.Red;



                foreach (var item  in group)

                {

                    Console.WriteLine(item.studentName);

                }

               

            }





     





        }

    }

}

Order by, Order by Descending, then by and then by Descending in linq c#

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;



namespace ConsoleApplication1

{

    class Program

    {

        static void Main(string[] args)

        {

            List<student> li = new List<student>()

          {



             new student() { studentID = 5, studentName = "Ron" , Age = 31 },

            new student() { studentID = 6, studentName = "Chris",  Age = 17 },

             new student() { studentID = 7, studentName = "Rob",Age = 19  },

            new student() { studentID = 8, studentName = "Rob",Age = 21  },

            new student() { studentID = 1, studentName = "John", Age = 18 },

            new student() { studentID = 2, studentName = "Steve",  Age = 21 },

            new student() { studentID = 3, studentName = "Bill",  Age = 25 },

            new student() { studentID = 4, studentName = "Ram" , Age = 20 },

         

            new student() { studentID = 9, studentName = "Bill",Age = 19  },



        };



           // var list = li.OrderBy(x => x.studentID).ToList();

          //  var list = li.OrderByDescending(x => x.studentName).ToList();

          //  var list = li.OrderByDescending(x => x.studentName).ThenBy(x=>x.Age).ToList();

            var list = li.OrderByDescending(x => x.studentName).ThenByDescending(x=>x.Age).ToList();

            foreach (var item in list)

            {

                Console.WriteLine("id: "+item.studentID+"---Name: "+item.studentName+"---age:"+item.Age);

            }



     





        }

    }

}

--------------------------------------------------------------------------------------------------------------

 public int studentID { get; set; }

        public string studentName { get; set; }

        public int Age { get; set; }