public ActionResult Create(Group_Master group_master)
        {
            if (ModelState.IsValid)
            {
                db.Group_Master.Add(group_master);
                db.SaveChanges();
                return RedirectToAction("Index");
            }

            return View(group_master);
        }
 public ActionResult Edit(Group_Master group_master)
 {
     if (ModelState.IsValid)
     {
         db.Entry(group_master).State = EntityState.Modified;
         db.SaveChanges();
         return RedirectToAction("Index");
     }
     return View(group_master);
 }