public ActionResult Edit(ProjectTag projecttag)
 {
     if (ModelState.IsValid)
     {
         db.Entry(projecttag).State = EntityState.Modified;
         db.SaveChanges();
         return RedirectToAction("Index");
     }
     ViewBag.ProjectID = new SelectList(db.Projects, "ProjectID", "alias", projecttag.ProjectID);
     ViewBag.TagID = new SelectList(db.Tags, "TagID", "name", projecttag.TagID);
     return View(projecttag);
 }
        public ActionResult Create(ProjectTag projecttag)
        {
            if (ModelState.IsValid)
            {
                db.ProjectTags.Add(projecttag);
                db.SaveChanges();
                return RedirectToAction("Index");  
            }

            ViewBag.ProjectID = new SelectList(db.Projects, "ProjectID", "alias", projecttag.ProjectID);
            ViewBag.TagID = new SelectList(db.Tags, "TagID", "name", projecttag.TagID);
            return View(projecttag);
        }