using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        IList<Student> studentList1 = new List<Student>() { 

            new Student() { StudentID = 1, StudentName = "John", Age = 18 } ,

            new Student() { StudentID = 2, StudentName = "Steve",  Age = 15 } ,

            new Student() { StudentID = 3, StudentName = "Bill",  Age = 25 } ,

            new Student() { StudentID = 5, StudentName = "Ron" , Age = 19 } 

        };

​

        IList<Student> studentList2 = new List<Student>() { 

            new Student() { StudentID = 3, StudentName = "Bill",  Age = 25 } ,

            new Student() { StudentID = 5, StudentName = "Ron" , Age = 19 } ,

            new Student() { StudentID = 6, StudentName = "Ram" , Age = 29 } 

        };

        var resultedCol = studentList1.Except(studentList2,new StudentComparer()); 

        foreach(Student std in resultedCol)

            Console.WriteLine(std.StudentName);

    }

}

​

public class Student 

{

    public int StudentID { get; set; }

    public string StudentName { get; set; }

    public int Age { get; set; }

}

​

class StudentComparer : IEqualityComparer<Student>

{

    public bool Equals(Student x, Student y)

    {

        if (x.StudentID == y.StudentID && x.StudentName.ToLower() == y.StudentName.ToLower())

            return true;

​

        return false;

    }

​

    public int GetHashCode(Student obj)

    {

        return obj.StudentID.GetHashCode();

    }

}