ASP.net MVC3如何编辑SQL数据库

Question

MovieStoreEntities MovieDb = new MovieStoreEntities();
public ActionResult Edit(int id)
{

    //var EditMovie1 = MovieDb
    AddMovieModel EditMovie = (from M in MovieDb.Movies
                               from C in MovieDb.Categories
                               where M.CategoryId == C.Id
                               where M.Id == id
                               select new AddMovieModel { Name = M.Name, Director = M.Director, Country = M.Country, categorie = C.CategoryName, Category = M.CategoryId }).FirstOrDefault();

    //AddMovieModel EditMovie1 = MovieDb.Movies.Where(m => m.Id == id).Select(m => new AddMovieModel {m.Id   }).First();
    List<CategoryModel> categories = MovieDb.Categories
       .Select(category => new CategoryModel { Category = category.CategoryName, id = category.Id })
       .ToList();

    ViewBag.Category = new SelectList(categories, "Id", "Category");


    return View(EditMovie);
}

//
// POST: /Default1/Edit/5

[HttpPost]
public ActionResult Edit(AddMovieModel Model2)
{
    List<CategoryModel> categories = MovieDb.Categories
        .Select(category => new CategoryModel { Category = category.CategoryName, id = category.Id })
        .ToList();
    ViewBag.Category = new SelectList(categories, "Id", "Category");



    if (ModelState.IsValid)
    {
        //MovieStoreEntities model = new MovieStoreEntities();






        MovieDb.SaveChanges();


        return View("Thanks2", Model2);
    }
    else
        return View();

}

This is the Code that I have wrote to edit Movie details and update database in the sql server. This dont have any compile errors, But It didnt update sql server database.

Answer 1

Presuming here you are updating a category you would need to do something like

 List<CategoryModel> categories = MovieDb.Categories
    .Select(category => new CategoryModel { Category = category.CategoryName, id = category.Id })
    .ToList();
ViewBag.Category = new SelectList(categories, "Id", "Category")
Category category = new Category()
category = categories.First(p=>p.CategoryId == Id);
category.Name = "New Name";
MovieDb.Categories.SaveChanges(category);
MovieDb.SaveChanges();

You will need to get the item you are wanting to edit...in this case a category which would be filtered from the list of categories. You can then call the savechanges method on that entity ie MovieDb.Categories.SaveChanges() and pass through the item that you want to update.

Answer 2

You need to use the Model2 object to create a new entity, add it to the ObjectContext and save the changes. You haven't written any code that should save anything to a database.