Question

我正在使用EF 4.1 Code First设置，这里是实体。

public class Vendor
{
    public int VendorId { get; set; }
    public string Name { get; set; }
    public virtual ICollection<VendorProduct> VendorProducts { get; set; }
}
public class VendorProduct
{
    public int VendorProductId { get; set; }
    public int ProductId { get; set; }
    public int VendorId { get; set; }
    public string VendorProductNumber { get; set; }
    public int Quantity { get; set; }
    public decimal SalesPrice { get; set; }
    public Product Product { get; set; }
    public Vendor Vendor { get; set; }
}
public class Product
{
    public int ProductId { get; set; }
    public string Name { get; set; }
    public string Manufacturer { get; set; }
    public string ManufacturerNumber { get; set; }
    public string UPC { get; set; }
    public decimal SalesPrice { get; set; }
    public string Description { get; set; }
    public virtual ICollection<VendorProduct> VendorProducts { get; set; }
}

以下是配置

public class VendorConfiguration : EntityTypeConfiguration<Vendor>
{
    public VendorConfiguration()
    {
        Property(p => p.Name).IsOptional().HasMaxLength(128);
    }
}
public class ProductConfiguration : EntityTypeConfiguration<Product>
{
    public ProductConfiguration()
    {
        //HasKey(p => p.ProductId);
        //HasMany(p => p.Images).WithOptional();
        Property(p => p.Name).IsOptional().HasMaxLength(128);
        Property(p => p.Manufacturer).IsOptional().HasMaxLength(64);
        Property(p => p.ManufacturerNumber).IsOptional().HasMaxLength(32);
        Property(p => p.UPC).IsOptional().HasMaxLength(32);
        Property(p => p.SalesPrice).IsOptional();
    }
}
    public VendorProductConfiguration()
    {
        //HasKey(v => v.VendorProductId);
        Property(o => o.Quantity).IsRequired();
        Property(o => o.SalesPrice).IsRequired();
        Property(o => o.VendorId).IsRequired();
        Property(o => o.ProductId).IsRequired();
        Property(o => o.VendorProductNumber).IsOptional().HasMaxLength(50);
        HasRequired(o => o.Product).WithMany(p => p.VendorProducts).HasForeignKey(o => o.ProductId).WillCascadeOnDelete(false);
    }

这是DbContext。

public class UbidContext : DbContext
{
    public IDbSet<Product> Products { get; set; }
    public IDbSet<Vendor> Vendors { get; set; }
    public IDbSet<VendorProduct> VendorProducts { get; set; }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        // Add any configuration or mapping stuff here
        modelBuilder.Configurations.Add(new VendorConfiguration());
        modelBuilder.Configurations.Add(new VendorProductConfiguration());
        modelBuilder.Configurations.Add(new ProductConfiguration());
    }


    public void Seed(UbidContext context)
    {
        //Create our indexes
        context.Database.ExecuteSqlCommand("CREATE INDEX IX_Products_Name ON Products (Name)");
        context.Database.ExecuteSqlCommand("CREATE INDEX IX_Products_Manufacturer ON Products (Manufacturer)");
        context.Database.ExecuteSqlCommand("CREATE INDEX IX_Products_ManufacturerNumber ON Products (ManufacturerNumber)");
        context.Database.ExecuteSqlCommand("CREATE INDEX IX_Products_UPC ON Products (UPC)");

        //Add vendors to the database
        AddVendors(context);
        context.SaveChanges();

        //Add products to the database
        AddProducts(context);
        context.SaveChanges();

        //Add vendor products to the database
        AddVendorProducts(context);
    }

    private static void AddVendors(UbidContext context)
    {
        new List<Vendor>
            {
                new Vendor()
                    {
                        Name = "TestVendor1",
                    },
                new Vendor()
                    {
                        Name = "TestVendor2",
                    },
                new Vendor()
                    {
                        Name = "TestVendor3",
                    }
            }.ForEach(v => context.Vendors.Add(v));
    }

    private static void AddProducts(UbidContext context)
    {
        Image[] images = new Image[1];
        images[0] = new Image
        {
            Url = "http://content.etilize.com/Thumbnail/10006997.jpg"
        };

        new List<Product>
            {
                new Product()
                    {
                        Manufacturer = "StarTech.com",
                        ManufacturerNumber = "SV211K",
                        Name = "StarTech.com SV211K KVM Switch - 2 x 1 - 2 x HD-15 Video",
                        UPC = "SV211K",
                        Images = images
                    },
                new Product()
                    {
                        Manufacturer = "Targus Group International",
                        ManufacturerNumber = "CBT300",
                        Name = "Targus BlackTop Standard Notebook Case - Clamshell - Carrying Strap - 5 Pocket - Nylon - Black, Blue",
                        UPC = "CBT300"
                    },
                new Product()
                    {
                        Manufacturer = "Lenovo Group Limited",
                        ManufacturerNumber = "31P8700",
                        Name = "Lenovo Optical ScrollPoint Pro Mouse - Optical - USB, PS/2",
                        UPC = "31P8700"
                    },
                new Product()
                    {
                        Manufacturer = "Epson Corporation",
                        ManufacturerNumber = "C823071",
                        Name = "Epson Serial Interface Board with 32K Buffer - 1 x RS-232 Serial",
                        UPC = "C823071"
                    },
                new Product()
                    {
                        Manufacturer = "Cisco Systems, Inc",
                        ManufacturerNumber = "WSX4013",
                        Name = "Cisco Catalyst 4000 Series Supervisor Engine II-Plus - 2 x GBIC, 1 x - Supervisor Engine",
                        UPC = "WSX4013"
                    }
            }.ForEach(p => context.Products.Add(p));
    }

    private static void AddVendorProducts(UbidContext context)
    {
        Random random = new Random();

        var vps = new List<VendorProduct>()
            {
                new VendorProduct()
                    {
                        ProductId = 1,
                        VendorId = 1,
                        Quantity = random.Next(3, 40),
                        SalesPrice = Converter.ConvertObjToDecimal(random.Next(20, 400)),
                    },
                new VendorProduct()
                    {
                        ProductId = 2,
                        VendorId = 1,
                        Quantity = random.Next(3, 40),
                        SalesPrice = Converter.ConvertObjToDecimal(random.Next(20, 400)),
                    },
                new VendorProduct()
                    {
                        ProductId = 3,
                        VendorId = 1,
                        Quantity = random.Next(3, 40),
                        SalesPrice = Converter.ConvertObjToDecimal(random.Next(20, 400)),
                    },
                 new VendorProduct()
                    {
                        ProductId = 4,
                        VendorId = 2,
                        Quantity = random.Next(3, 40),
                        SalesPrice = Converter.ConvertObjToDecimal(random.Next(20, 400)),
                    },
                new VendorProduct()
                    {
                        ProductId = 4,
                        VendorId = 3,
                        Quantity = random.Next(3, 40),
                        SalesPrice = Converter.ConvertObjToDecimal(random.Next(20, 400)),
                    }
            };
        foreach (var vp in vps)
            context.VendorProducts.Add(vp);
    }

    public class DropCreateIfChangeInitializer : DropCreateDatabaseIfModelChanges<UbidContext>
    {
        protected override void Seed(UbidContext context)
        {
            context.Seed(context);

            base.Seed(context);
        }
    }

    static UbidContext()
    {
        Database.SetInitializer<UbidContext>(new DropCreateIfChangeInitializer());
    }
}

现在，当它到达VendorProducts时，第一个添加得很好，但第二个不会保存，因为看起来EF没有设置Vendor对象，我看到的模式是对于在同一上下文中的前一个实体上使用vendorid和/或productid时添加的每个vendorproduct，它不会填充供应商或产品，因此它将其设置为null。从我的代码中可以看出，我在下面显式设置VendorId，但是当EF将数据发送到db时，VendorId为null。如果您需要更多信息，请告诉我。

由于

Answer 1

我已将您的代码复制并粘贴到使用EF 4.1的控制台应用程序中。当我运行它时，我在数据库（SQL Server 2008 R2 Express）中得到了这个结果：

EFSeedTest

我只删除了图片中的内容和Converter.ConvertObjToDecimal（没编译，我直接使用random.Next）。

我认为这是您对代码的期望。你得到另一个结果吗？

EF覆盖了我设置的属性

1 个答案: