根据实体代码优先方法播种我的数据库

Question

So after I had the wizard create models from an existing database my Configuration.cs was

namespace SnakeGame.Migrations
{
    using System;
    using System.Data.Entity;
    using System.Data.Entity.Migrations;
    using System.Linq;

    internal sealed class Configuration : DbMigrationsConfiguration<SnakeGame.Models.ApplicationDbContext>
    {
        public Configuration()
        {
            AutomaticMigrationsEnabled = false;
        }

        protected override void Seed(SnakeGame.Models.ApplicationDbContext context)
        {
            //  This method will be called after migrating to the latest version.

            //  You can use the DbSet<T>.AddOrUpdate() helper extension method 
            //  to avoid creating duplicate seed data. E.g.
            //
            //    context.People.AddOrUpdate(
            //      p => p.FullName,
            //      new Person { FullName = "Andrew Peters" },
            //      new Person { FullName = "Brice Lambson" },
            //      new Person { FullName = "Rowan Miller" }
            //    );
            //
        }
    }
}

and the model of my database was

namespace SnakeGame.Migrations
{
    using System;
    using System.Data.Entity;
    using System.ComponentModel.DataAnnotations.Schema;
    using System.Linq;

    public partial class SnakeDB : DbContext
    {
        public SnakeDB()
            : base("name=SnakeDB")
        {
        }

        public virtual DbSet<BannedIP> BannedIPs { get; set; }
        public virtual DbSet<GameLog> GameLogs { get; set; }
        public virtual DbSet<IP> IPs { get; set; }
        public virtual DbSet<Score> Scores { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Entity<GameLog>()
                .Property(e => e.logText)
                .IsUnicode(false);

            modelBuilder.Entity<IP>()
                .HasMany(e => e.BannedIPs)
                .WithRequired(e => e.IP)
                .WillCascadeOnDelete(false);

            modelBuilder.Entity<Score>()
                .Property(e => e.name)
                .IsUnicode(false);
        }
    }
}

Trying to follow the commented out instructions, I changed the body of protected override void Seed(SnakeGame.Models.ApplicationDbContext context) to

        context.IPs.AddOrUpdate(
            i => i.id,
            new IP { id = 1, byte1 = 4, byte2 = 35, byte3 = 241, byte4 = 179 },
            new IP { id = 2, byte1 = 172, byte2 = 16, byte3 = 254, byte4 = 1 }
        );

        context.BannedIPs.AddOrUpdate(
            i => i.id,
            new BannedIP { id = 1, ipId = 1}
        );

        context.Score.AddOrUpdate(
            s => s.id,
            new Score {  id = 1, score1 = 12, name = "John Skeet" },
            new Score {  id = 2, score1 = 1923, name = "Steve Ballmer"}
        );

but I'm getting errors on each of context.IPs , context.BannedIP s and context.Score . The error I'm getting is

SnakeGame.Models.ApplicationDbContext does not contain a definition for ...

and I'm trying to figure out how to fix it. The full code of my Migrations folder can be seen here . I think I've royally messied up my project by all these attempts at code-first migration. Blah.

Answer 1

Your entities are all defined in the SnakeDb context, not ApplicationDbContext so change your seed to

protected override void Seed(SnakeGame.Migrations.SnakeDb context)
...

After you reverse engineer, you may want to move things into whatever structure you want your app to have. For me, I copy the POCOs to a separate "Entity" project and then move the EF and context stuff to a "Data" project, but you could also just move them into different folders.

Second, since you reverse engineered the database, you will need a baseline initial migration. You can either comment out the Up() and Down() code or you can generate via

Add-Migration InitialCreate –IgnoreChanges

https://msdn.microsoft.com/en-us/data/dn579398.aspx#option1

Answer 2

Did you update your DB with your migrations?? I have an example of the commands in my proyects

/*
* X DATA CONTEXT 
*/

//this command enables migrations
Enable-Migrations -StartUpProjectName X.Web -ProjectName X.DAL.Repository -EnableAutomaticMigrations -ContextTypeName XDataContext -Verbose -MigrationsDirectory:XDataContextMigrations

//this command create a new migration, please set up the name of the DBMigration
Add-Migration [NAME] -StartUpProjectName X.Web -ProjectName X.DAL.Repository -ConfigurationTypeName XUpdateDatabaseInitializer -Verbose 

//this command updates the current database
Update-Database -StartUpProjectName X.Web -ProjectName X.DAL.Repository -ConfigurationTypeName XUpdateDatabaseInitializer -Verbose 

//this command rollbacks the current Database to Specific Target applying Down() methods
Update-Database –TargetMigration: SpecificTargetMigrationName -StartUpProjectName X.Web -ProjectName X.DAL.Repository -ConfigurationTypeName XUpdateDatabaseInitializer -Verbose 

So, if you already updated your DB I'd suggest you to completely delete your current DB and recreate it using Migrations commands...

Hope it helps.