如何在实体框架中添加种子方法

本文关键字:添加 种子 子方法 框架 实体 | 更新日期: 2023-09-27 18:12:33

我试图用实体框架运行代码优先迁移。我启用、添加和更新。当我更新时,它说它运行种子方法并且没有错误,但是当我查看表中的数据时,没有任何错误。

这是我的播种机:

public static class Seeder
{
    public static void Seed(ApplicationDbContext context)
    {
        context.Props.AddOrUpdate(
            p => p.PropId,
            new Prop() { PropName = "sharpie" },
            new Prop() { PropName = "coin" },
            new Prop() { PropName = "playing cards" },
            new Prop() { PropName = "coffee mug" },
            new Prop() { PropName = "phone" },
            new Prop() { PropName = "keys" },
            new Prop() { PropName = "sunglasses" },
            new Prop() { PropName = "headphones" },
            new Prop() { PropName = "ring" },
            new Prop() { PropName = "lighter" }
            );
        context.Theories.AddOrUpdate(
            t => t.TheoryId,
            new Theory()
            {
               // TheoryId = 0,
                TheoryName = "Production",
                TheoryDescription = "Make it appear out of nowhere!"
            },
            new Theory()
            {
               // TheoryId = 1,
                TheoryName = "Vanish",
                TheoryDescription = "Make it vanish into thin air!"
            },
            new Theory()
            {
               // TheoryId = 2,
                TheoryName = "Transportation",
                TheoryDescription = "Make it vanish, and then reappear somewhere impossible!"
            },
            new Theory()
            {
               // TheoryId = 3,
                TheoryName = "Transformation", // This uses TWO props
                TheoryDescription = "Cause one of these items to change into the other item!"
            },
            new Theory()
            {
               // TheoryId = 4,
                TheoryName = "Multiplication",
                TheoryDescription = "Magically duplicate this item again and again!"
            },
            new Theory()
            {
               // TheoryId = 5,
                TheoryName = "Penetration", // This uses TWO props
                TheoryDescription = "Cause the two items to inexplicably pass through each other"
            },
            new Theory()
            {
               // TheoryId = 6,
                TheoryName = "Restoration",
                TheoryDescription = "Destroy the item in some way. Restore it."
            },
            new Theory()
            {
               // TheoryId = 7,
                TheoryName = "Levitation",
                TheoryDescription = "Make the item float in mid-air!"
            });
        //////////////////////////////////////////// The following seeds user data
        // ApplicationUser table seeder
        UserStore<ApplicationUser> userStore = new UserStore<ApplicationUser>(context);
        UserManager<ApplicationUser> userManager = new UserManager<ApplicationUser>(userStore);
        RoleStore<Role> roleStore = new RoleStore<Role>(context);
        RoleManager<Role> roleManager = new RoleManager<Role>(roleStore);
        if (!roleManager.RoleExists("Admin"))
            roleManager.Create(new Role { Name = "Admin" });
        if (!roleManager.RoleExists("User"))
            roleManager.Create(new Role { Name = "User" });
        IdentityResult result = null; // Sets the result to null. Used for error checking.
        /////////// Admin (1)
        ApplicationUser admin1 = userManager.FindByName("MagicRawb");
        if (admin1 == null)
        {
            admin1 = new ApplicationUser
            {
                FirstName = "Rob",
                LastName = "Greenwald",
                UserName = "magicrawb",
                Email = "magicrawb@test.com",
                Gender = Gender.Male
            };
        }
        result = userManager.Create(admin1, "asdfasdf");
        if (!result.Succeeded)
        {
            string error = result.Errors.FirstOrDefault();
            throw new Exception(error);
        }
        userManager.AddToRole(admin1.Id, "Admin"); // Add user1 to Admin role
        admin1 = userManager.FindByName("MagicRawb"); // Assign user1 data to variable user1
        /////////// Admin (2)
        ApplicationUser admin2 = userManager.FindByName("admin2");
        if (admin2 == null)
        {
            admin2 = new ApplicationUser
            {
                FirstName = "Bekah",
                LastName = "Cellz",
                UserName = "admin2",
                Email = "admin2@test.com",
                Gender = Gender.Female
            };
        }
        result = userManager.Create(admin2, "asdfasdf");
        if (!result.Succeeded)
        {
            string error = result.Errors.FirstOrDefault();
            throw new Exception(error);
        }
        userManager.AddToRole(admin2.Id, "Admin"); // Add user1 to Admin role
        admin1 = userManager.FindByName("admin2"); // Assign user1 data to variable user1
        /////////// User (1)
        ApplicationUser user1 = userManager.FindByName("user1");
        if (user1 == null)
        {
            user1 = new ApplicationUser
            {
                FirstName = "Lance",
                LastName = "Burton",
                UserName = "user1",
                Email = "user1@test.com",
                Gender = Gender.Male
            };
        }
        result = userManager.Create(user1, "asdfasdf");
        if (!result.Succeeded)
        {
            string error = result.Errors.FirstOrDefault();
            throw new Exception(error);
        }
        userManager.AddToRole(user1.Id, "User"); // Add user1 to Admin role
        user1 = userManager.FindByName("user1"); // Assign user1 data to variable user1
        /////////// User (2)
        ApplicationUser user2 = userManager.FindByName("user2");
        if (user2 == null)
        {
            user2 = new ApplicationUser
            {
                FirstName = "David",
                LastName = "Stone",
                UserName = "user2",
                Email = "user2@test.com",
                Gender = Gender.Male
            };
        }
        result = userManager.Create(user2, "asdfasdf");
        if (!result.Succeeded)
        {
            string error = result.Errors.FirstOrDefault();
            throw new Exception(error);
        }
        userManager.AddToRole(user1.Id, "User"); // Add user1 to Admin role
        user2 = userManager.FindByName("user2"); // Assign user1 data to variable user1
        context.SaveChanges();
    }
}

这里是DbContext:

public ApplicationDbContext()
    : base("DefaultConnection", throwIfV1Schema: false)
{
    this.Configuration.LazyLoadingEnabled = false;
}
public static ApplicationDbContext Create()
{
    return new ApplicationDbContext();
}
public IDbSet<Prop> Props { get; set; }
public IDbSet<Theory> Theories { get; set; }
public IDbSet<NewTrick> NewTricks { get; set; }
我不太确定我在这里做错了什么。我很乐意提供我可能缺少的任何信息。

如何在实体框架中添加种子方法

你应该添加一个像

这样的配置类
internal class Configuration : DbMigrationsConfiguration<ApplicationDbContext>
{
    protected override void Seed(ApplicationDbContext context)
    {
          //seed code here
    }
}

,然后有一个像

这样的初始化类
public class MyInitializer : MigrateDatabaseToLatestVersion<ApplicationDbContext, Configuration>
{
}

,最后在应用程序启动时设置EF数据库的初始化器

Database.SetInitializer(new MyInitializer());

您已经使用以下代码行两次将UserRole添加到UserManager中userManager.AddToRole(user1.Id, "User")这可能是冲突的原因。

要准确地复制上面的代码你张贴,在一个新的文件,看看第159和184行。