LINQ ThenBy Descending Operator

In LINQ, ThenByDescending operator is used to implement the sorting on multiple fields in the list/ collection, and by default, ThenByDescending operator will sort the list of items in descending order. In LINQ, we use the ThenByDescending operator along with OrderBy operator.

In LINQ, ThenByDescending operator is used to specify the second sorting condition to be the descending, and OrderBy operator is used to specify the condition on primary sorting.

Syntax of LINQ ThenByDescending operator

The Syntax of using the LINQ ThenByDescending Operator to implement the sorting on list/collection of the items along with OrderBy operator.

C# Code

  var studentname = Objstudent.OrderBy(x => x.Name).ThenByDescending(x => x.RoleId);

From the above example, it shows that we defined first the sorting condition wiith OrderBy Operator and second condition with ThenByDescending operator. We are sorting the list of items using "Name" and we added another field "RoleId" by using ThenByDescending Operator.

We will see with the help of an example.

Example of LINQ ThenByDescending operator

Here is the example of LINQ ThenByDescending operator to sort the list/collection of items based on the multiple fields is:

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

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
//Create object ObjStudent of the Student class having the list of the student information
            List<Student> Objstudent = new List<Student>()
            {
                new Student() { RoleId=1, Name = "Suresh Dasari", Gender = "Male", Subjects = new List<string> { "Mathematics","Physics" } },
                new Student() { RoleId=2, Name = "Rohini Alavala", Gender = "Female", Subjects = new List<string> { "Entomology", "Botany" } },
                new Student() { RoleId=3, Name = "Praveen Kumar", Gender = "Male", Subjects = new List<string> { "Computers","Operating System", "Java" } },
                new Student() { RoleId=4, Name = "Sateesh Chandra", Gender = "Male", Subjects = new List<string> { "English", "Social Studies", "Chemistry" } },
                new Student() { RoleId=5, Name = "Madhav Sai", Gender = "Male", Subjects = new List<string> { "Accounting", "Charted" } }
            };
    //ThenByDescending() operator is used to sort the information of the student in the descending form
                var studentname = Objstudent.OrderBy(x => x.Name).ThenByDescending(x => x.RoleId);
                foreach (var student in studentname)
                {
                    Console.WriteLine("Name={0} StudentId={1}", student.Name, student.RoleId);
                }
                    Console.ReadLine();
         }
     }
    //create a student class
    class Student
    {
        public int RoleId { get; set; }
        public string Name { get; set; }
        public string Gender { get; set; }
        public List<string> Subjects { get; set; }
    }
}

In the above example, we are sorting the "ObjStudent" list of items by using the multiple fields Name, RoleId.

OUTPUT: