gistfile1.cs

    // StudentDetails.cs
    partial class StudentDetails
    {
        public void Display()
        {
            Console.WriteLine("Student Roll Number: " + _rollNo);
            Console.WriteLine("Student Name: " + _studName);
        }
    }
    // StudentDetails1.cs
    partial class StudentDetails
    {
        private int _rollNo;
        private string _studName;
        public StudentDetails(int num, string name)
        {
            _rollNo = num;
            _studName = name;
        }
    }

    public class Students
    {
        static void Main(string[] args)
        {
            StudentDetails objStudents = new StudentDetails(20,"Frank");
            objStudents.Display();
        }
    }