ASP.NET MVC Call action when a specific change is made in edit : I created a Crud object to track employee holidays, in my HTTP Post EDIT method I'd like to use an email action (which already works) for when a manager edits a request to change the boolean status from `pending` to `approved`.

Here's what I attempted but my c# is not up to scratch just yet. 

    [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Edit([Bind(Include = "RequestID,EmployeeID,StartDate,FinishDate,HoursTaken,Comments,YearCreated,MonthCreated,DayCreated,YearOfHoliday,Approved,SubmittedBy,ApprovedBy")] HolidayRequestForm holidayRequestForm)
        {
            if (ModelState.IsValid)
            {

                if (Session["Name"] == null)
                {
                    TempData["msg"] = "Your Session Expired - Please Login";
                    return RedirectToAction("Login", "Account");
                }

                string name = Session["Name"].ToString();

                var approvedby = db.Employees.Where(s => s.Email.Equals(name)).Select(s => s.Email).FirstOrDefault();
                holidayRequestForm.ApprovedBy = approvedby;

                db.Entry(holidayRequestForm).State = EntityState.Modified;
                db.SaveChanges();

                if {

                    db.HolidayRequestForms.Select(h => h.Approved) == true;
                    SendMailToManager();

                }
                
                
                return RedirectToAction("Index");
            }
            ViewBag.EmployeeID = new SelectList(db.Employees, "EmployeeID", "FullName", holidayRequestForm.EmployeeID);
            return View(holidayRequestForm);
        }

How do I get it to send the email (call the SendMailToManager() action) when a manager edit the request's status to true?