How to pass reference by object in asp.net mvc?

Question

Hi Team

 

I have a method, but i want to pass reference byy object, meaning i have declared it as a string, but when i insert raw data it stored to the db, that is not what i want. I want when a user insert any object name it must store it to the record.

   [Route("Home/AllCourses")]
        public ActionResult CoursesRegistration(RegCoursesViewModel eNtsaRegistration)
        {
            string courseName = "TestData"; // This stores to the db.
string courseName = string.empty; // This is not stored to the record
            eNtsaRegistration.Courses = new eNtsaCourses();
            if (ModelState.IsValid)
            {

                eNtsaRegistration.Courses.Course = courseName;
                eNtsaRegistration.Courses.Id = Guid.NewGuid();
                cb.Courses.Add(eNtsaRegistration.Courses);
                cb.SaveChanges();
            }

            return RedirectToAction("AllCourses");
        }