How to rollback a transaction in EntityFramework?

Question

I have two database tables named Courses and Transactions.Courses stores the details of a particular course and Transactions table stores the details of the transactions performed by a particular user.

My question is how can I make sure that entry in the CourseTable is saved only when transactions(add,edit,delete) regarding that particular course is saved into the TransactionTable

CourseTable is

TransactionTable is

Controller is

     POST: /Course/Add
    [HttpPost]
    public ActionResult Add(CourseVM _mdlCourseVM) 
    {
            string actionName=this.ControllerContext.RouteData.Values["action"].ToString();
                string controllerName=this.ControllerContext.RouteData.Values["controller"].ToString();

                Course _course = new Course();
                _course.Duration = _mdlCourseVM.Course.Duration;
                _course.DurationMode = _mdlCourseVM.DurationModeId;
                _course.InstalmentFee = _mdlCourseVM.Course.InstalmentFee;
                _course.Name = _mdlCourseVM.Course.Name;
                _course.SingleFee = _mdlCourseVM.Course.SingleFee;

                _db.Courses.Add(_course);

                int i = _db.SaveChanges();

                if (i > 0)
                {
                    Common _cmn=new Common();

                    //Add the transaction details 
                    int k=_cmn.AddTransactions(actionName,controllerName,"");

                   //Want to commit changes to the coursetable here
                   if(k>0){                         
                      _db.commitTransaction()
                   }
                   //Want to rollback the committed transaction
                   else{                        
                      _db.rollbackTransaction();
                   }

                }
    }

Answer 1

I solved the above scenario by using System.Transactions.Hope anyone with same scenario find it useful.

 using (TransactionScope _ts = new TransactionScope())
                {
                    string actionName = this.ControllerContext.RouteData.Values["action"].ToString();
                    string controllerName = this.ControllerContext.RouteData.Values["controller"].ToString();

                    Course _course = new Course();
                    _course.Duration = _mdlCourseVM.Course.Duration;
                    _course.DurationMode = _mdlCourseVM.DurationModeId;
                    _course.InstalmentFee = _mdlCourseVM.Course.InstalmentFee;
                    _course.Name = _mdlCourseVM.Course.Name;
                    _course.SingleFee = _mdlCourseVM.Course.SingleFee;

                    _db.Courses.Add(_course);
                    int i = _db.SaveChanges();

                    if (i > 0)
                    {
                        Common _cmn = new Common();
                        int k = _cmn.AddTransactions(actionName, controllerName, "",Session["UserId"].ToString());
                        if (k > 0)
                        {
                            _ts.Complete();
                            return Json(new { message = "success" }, JsonRequestBehavior.AllowGet);
                        }
                        else
                        {
                            return Json(new { message = "error" }, JsonRequestBehavior.AllowGet);
                        }

                    }
                    else 
                    {
                        return Json(new { message = "error" }, JsonRequestBehavior.AllowGet);
                    }

                }
            }