Question

在我的普通.NET框架中，我在Configuration.cs中使用了以下代码：

protected override void Seed(Athlosify.Models.AthlosifyContext context)
    {
        var golfCourses = new List<GolfCourse>
        {
            new GolfCourse { Name = "Bonnie Doon Golf Club", Description = "N/A", Address = "38 Banks Ave", Suburb = "Pagewood", State="NSW", Postcode = "2035", Country = "Australia", Latitude=-33.935189, Longitude=151.222372  },
            new GolfCourse { Name = "Beverly Park Golf Club", Description = "N/A", Address = "87 Jubilee Avenue", Suburb = "Beverly Park", State="NSW", Postcode = "2217", Country = "Australia", Latitude=-33.975506, Longitude=151.131691  }

        };
        golfCourses.ForEach(s => context.GolfCourses.AddOrUpdate(p => p.GolfCourseID, s));
        context.SaveChanges();

        var golfRoundCategories = new List<GolfRoundCategory>
        {
            new GolfRoundCategory { Name = "Competition - Stroke", Description = "N/A" },
            new GolfRoundCategory { Name = "Competition - Stableford", Description = "N/A" },
            new GolfRoundCategory { Name = "Competition - Ambrose", Description = "N/A" },
            new GolfRoundCategory { Name = "Competition - Foresome", Description = "N/A" },
            new GolfRoundCategory { Name = "Practice - 2 Ball Best Balls", Description = "N/A" },
            new GolfRoundCategory { Name = "Practice - 2 Ball Worst Balls", Description = "N/A" },
        };
        golfRoundCategories.ForEach(s => context.GolfRoundCategories.AddOrUpdate(p => p.GolfRoundCategoryID, s));
        context.SaveChanges();

        var golfRounds = new List<GolfRound>
        {
            new GolfRound { Name = "Bonnie Doon GC Practice", Notes = "N/A", UserID = Guid.Parse("7dd950ad-d7b0-448a-b689-db3947e31bec"),
                        GolfCourseID = golfCourses.Single(c => c.Name == "Bonnie Doon Golf Club" ).GolfCourseID,
                        DailyHandicap = 21, GolfRoundCategoryID = golfRoundCategories.Single(c => c.Name == "Practice - 2 Ball Best Balls" ).GolfRoundCategoryID,
                        TeeOffUTC = DateTime.Parse("2018-07-22 15:00") },
        };
        golfRounds.ForEach(s => context.GolfRounds.AddOrUpdate(p => p.GolfRoundID, s));
        context.SaveChanges();

尝试在.Net Core 2.1中进行播种，然后再获取该值：

GolfCourseID = golfCourse.Single（c => c.Name ==“ Bonnie Doon高尔夫俱乐部”）.GolfCourseID

和

GolfRoundCategoryID = golfRoundCategories.Single（c => c.Name ==“ Practice-2 Ball Best Balls”）。GolfRoundCategoryID

？!!？！

public static void Seed(this ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<GolfCourse>().HasData(
            new GolfCourse { Name = "Bonnie Doon Golf Club", Description = "N/A", Address = "38 Banks Ave", Suburb = "Pagewood", State = "NSW", Postcode = "2035", Country = "Australia", Latitude = -33.935189, Longitude = 151.222372 },
            new GolfCourse { Name = "Beverly Park Golf Club", Description = "N/A", Address = "87 Jubilee Avenue", Suburb = "Beverly Park", State = "NSW", Postcode = "2217", Country = "Australia", Latitude = -33.975506, Longitude = 151.131691 }

        );
        modelBuilder.Entity<GolfRoundCategory>().HasData(
            new GolfRoundCategory { Name = "Competition - Stroke", Description = "N/A" },
            new GolfRoundCategory { Name = "Competition - Stableford", Description = "N/A" },
            new GolfRoundCategory { Name = "Competition - Ambrose", Description = "N/A" },
            new GolfRoundCategory { Name = "Competition - Foresome", Description = "N/A" },
            new GolfRoundCategory { Name = "Practice - 2 Ball Best Balls", Description = "N/A" },
            new GolfRoundCategory { Name = "Practice - 2 Ball Worst Balls", Description = "N/A" }
        );

        modelBuilder.Entity<GolfRound>().HasData(
            new GolfRound
            {
                Name = "Bonnie Doon GC Practice",
                Notes = "N/A",
                UserID = Guid.Parse("7dd950ad-d7b0-448a-b689-db3947e31bec"),
                GolfCourseID = golfCourse.Single(c => c.Name == "Bonnie Doon Golf Club").GolfCourseID,
                DailyHandicap = 21,
                GolfRoundCategoryID = golfRoundCategories.Single(c => c.Name == "Practice - 2 Ball Best Balls").GolfRoundCategoryID,
                TeeOffUTC = DateTime.Parse("2018-07-22 15:00")
            },
        );

    }

Answer 1

在EF Core中，种子数据是迁移的组成部分。就像数据库架构更改一样，种子数据的更改也会被检测到并嵌入到迁移中。这样，就没有 DbContext 可以运行查询或检索由数据库引擎自动生成的ID。

您需要为自动生成的键列设置显式ID值，以便能够引用这些实体：

var golfCourse1 = new GolfCourse { GolfCourseID = 1, Name = "Bonnie Doon Golf Club", Description = "N/A", Address = "38 Banks Ave", Suburb = "Pagewood", State = "NSW", Postcode = "2035", Country = "Australia", Latitude = -33.935189, Longitude = 151.222372 };

modelBuilder.Entity<GolfCourse>().HasData(
    golfCourse1,
    // ...
);

var golfRoundCategory5 = new GolfRoundCategory { GolfRoundCategoryID = 5, Name = "Practice - 2 Ball Best Balls", Description = "N/A" };

modelBuilder.Entity<GolfRoundCategory>().HasData(
    // ...
    golfRoundCategory5,
    // ...
);

modelBuilder.Entity<GolfRound>().HasData(
    new GolfRound
    {
        Name = "Bonnie Doon GC Practice",
        Notes = "N/A",
        UserID = Guid.Parse("7dd950ad-d7b0-448a-b689-db3947e31bec"),
        GolfCourseID = golfCourse1.GolfCourseID,
        DailyHandicap = 21,
        GolfRoundCategoryID = golfRoundCategory5.GolfRoundCategoryID,
        TeeOffUTC = DateTime.Parse("2018-07-22 15:00")
    },
 );

如何在EF Core 2.1中播种

1 个答案: