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我正在使用捆绑包：ASP.NET MVC3、SQL Server 2012、EF5。当我尝试将值保存到我的数据库中时，我只能将 Book 的属性 IsSelected 保存在我的数据库中的 Books 表中，StudentName 无法保存，也无法将数据保存到数据库中的 StudentBooks 表中，其中包含 StudentId 和 BookId，多对的键-很多关系，有什么想法吗？

public class CheckboxController : Controller
{
    EFDbContext context = new EFDbContext(ConfigurationManager.ConnectionStrings[1].ConnectionString);

    //
    //GET: /Checkbox/

    public ActionResult Index()
    {
        ViewModelData vmd = new ViewModelData();
        List<Book> bookList = new List<Book>();

        using (EFDbContext te = new EFDbContext(ConfigurationManager.ConnectionStrings[1].ConnectionString))
        {
            var student = te.Students.First();
            vmd.StudentName = student.StudentName;

            var data = te.Books.ToList();
            foreach (var d in data) {
                Book book = new Book();
                book.BookName = d.BookName;
                book.IsSelected = false;
                book.BookId = d.BookId;
                bookList.Add(book);
            }
        }

        vmd.Books = bookList;

        return View(vmd);
    }

    //
    //GET: /Checkbox/

    [HttpPost]
    public ActionResult Index(ViewModelData vm)
    {
        foreach (var book in vm.Books) {
            context.Books.First(x => x.BookId == book.BookId).IsSelected = book.IsSelected;
        }


        context.SaveChanges();
        return View(vm);
    }
}

public class ViewModelData
{
    public string StudentName { get; set; }
    public List<Book> Books { get; set; }
}

看法

    @model UsingEFNew.Controllers.ViewModelData

@{
    ViewBag.Title = "Example";
}

@using (Html.BeginForm("Index", "Checkbox", null, FormMethod.Post))
{
<div>Your Name:</div>
    <div>
        @Html.TextBoxFor(model => model.StudentName)
    </div>

    for (int i = 0; i < Model.Books.Count; i++) {
    @Html.CheckBoxFor(m => Model.Books[i].IsSelected)
    @Html.DisplayFor(m => Model.Books[i].BookName)
    @Html.HiddenFor(m => Model.Books[i].BookId)
    @Html.HiddenFor(m => Model.Books[i].BookName)
@:</br>
}

}

我的模特

public class Book {
    public int BookId { get; set; }
    public string BookName { get; set; }
    public bool IsSelected { get; set; }

    public ICollection<Student> Students { get; set; }
}

public class Student {
        public int StudentId { get; set; }
        public string StudentName { get; set; }

        public ICollection<Book> Books { get; set; }
        public ICollection<City> Cities { get; set; }
    }
4

1 回答 1

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在您的 [HttpPost]Index 中，您不会从 ViewDataModel 中获取学生姓名并将其推送到任何学生实体中。

[HttpPost]
public ActionResult Index(ViewModelData vm)
{
    foreach (var book in vm.Books) {
        context.Books.First(x => x.BookId == book.BookId).IsSelected = book.IsSelected;
    }        

    var student = context.Students.First();
    student.Name = vm.StudentName;//now I've actually changed the student entity and changes will be pushed to database on Save()

    context.SaveChanges();
    return View(vm);
}

但是，看起来您并没有真正利用它们之间的关系。您只需抓住第一个学生，而不是使用从书到学生的关系。我在这里做了同样的事情，只是为了演示将视图模型中的值映射到实体中。

于 2013-07-01T18:58:50.330 回答