public ActionResult ProjectUser(string Id, AdminProjectUserAssignViewModel model) { var user = db.Users.Find(model.User.Id); foreach (var project in user.Projects.ToList()) { if (!model.SelectedProjects.Contains(project.Id)) { phelper.RemoveProjectFromUser(user.Id, project.Id); } } foreach (var projectId in model.SelectedProjects) { if (model.SelectedProjects.Contains(projectId)) { phelper.AddProjectToUser(user.Id, projectId); } } db.SaveChanges(); return(RedirectToAction("Index")); }