1. 首先创建一个种子数据类 SeedData，并在其中添加你所需的数据：

public static class SeedData
{
    public static void Seed(this ModelBuilder modelBuilder)
    {
        modelBuilder.Entity().HasData(
            new Author { Id = 1, Name = "Jane Austen" },
            new Author { Id = 2, Name = "Charles Dickens" },
            new Author { Id = 3, Name = "Miguel de Cervantes" }
        );

        modelBuilder.Entity().HasData(
            new Book { Id = 1, Title = "Pride and Prejudice", AuthorId = 1 },
            new Book { Id = 2, Title = "Sense and Sensibility", AuthorId = 1 },
            new Book { Id = 3, Title = "David Copperfield", AuthorId = 2 },
            new Book { Id = 4, Title = "Don Quixote", AuthorId = 3 }
        );
    }
}

2. 在配置DbContext时，在OnModelCreating方法中调用Seed方法：

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity().ToTable("Author");
    modelBuilder.Entity().ToTable("Book");

    modelBuilder.Seed();
}

3. 最后在运行应用程序之前使种子数据生效，可在Startup.cs文件中使用如下方法：

public void Configure(IApplicationBuilder app, IHostingEnvironment env, ApplicationDbContext context)
{
    context.Database.Migrate();
    app.UseMvc();
}