Question

我正在使用asp.net core 2和ef core 2开发一个API项目。当我每次想要删除所有表然后创建时进行迁移时，我想只包含更改。

public class TicketingContext : DbContext
{
    public TicketingContext(DbContextOptions<TicketingContext> options) : base(options)
    {
        Database.Migrate();
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {            
    }

    public DbSet<User> Users { get; set; }
    public DbSet<Country> Countries { get; set; }     
    public DbSet<TZone> TZones { get; set; }
    public DbSet<Company> Companies { get; set; }
    public DbSet<Point> Points { get; set; }
    public DbSet<Bus> Buses { get; set; }

}

这是我的启动类和DesignTimeDbContextFactory

public class Startup
{
    public Startup(IConfiguration configuration)
    {
        Configuration = configuration;
    }
    public IConfiguration Configuration { get; }

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddMvc();           
    }

    public void Configure(IApplicationBuilder app, IHostingEnvironment env, TicketingContext context)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }           
        app.UseMvc();                     
    }
}

这是 DesignTimeDbContextFactory实现

public class DesignTimeDbContextFactory : IDesignTimeDbContextFactory<TicketingContext>
{
    public TicketingContext CreateDbContext(string[] args)
    {
        IConfigurationRoot configuration = new ConfigurationBuilder()
            .SetBasePath(Directory.GetCurrentDirectory())
            .AddJsonFile("appsettings.json")
            .Build();

        var builder = new DbContextOptionsBuilder<TicketingContext>();

        var connectionString = configuration.GetConnectionString("DefaultConnection");

        builder.UseSqlServer(connectionString);

        return new TicketingContext(builder.Options);
    }
}

Answer 1

在Startup.cs中编辑Configure方法。将TicketingContext添加为参数：

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

Asp.net Core 2迁移无法正常工作

1 个答案: