註冊實體映射

Question

我正在asp.net核心項目使用EF核心。我通過覆蓋上下文類中的OnModelCreating函數來映射我的實體。我可以輕鬆地手動映射這些實體。好了，我會更好地後我的代碼，並解釋..

這是我在我的上下文類所做的：

protected override void OnModelCreating(ModelBuilder builder) 
    {   
     base.OnModelCreating(builder); 
     //builder.RegisterEntityMapping<CodeTable, CodeTableMap>(); 
     builder.RegisterEntityMapping<Country, CountryMap>(); 
     builder.RegisterEntityMapping<State, StateMap>(); 
     builder.RegisterEntityMapping<City, CityMap>(); 
     builder.RegisterEntityMapping<User, UserMap>(); 
     builder.RegisterEntityMapping<Prospect, ProspectMap>(); 
    } 

Country.cs

public class Country:BaseEntity 
{ 

    public string CountryCode { get; set; } 
    public string CountryName { get; set; } 
    public string Currency { get; set; } 
    public string CurrencyName { get; set; } 
    public string UnitOfMeasure { get; set; } 
    public string TelephoneCountryCode { get; set; } 
    public string CurrencySymbol { get; set; } 

    public virtual ICollection<State> States { get; set; } 
    public virtual ICollection<City> Cities { get; set; } 
} 

CountryMap.cs

public class CountryMap : QuantumEntityTypeConfiguration<Core.Domain.Country> 
{ 
    public override void Map(EntityTypeBuilder<Core.Domain.Country> builder) 
    { 
     builder.ToTable("Country"); 
     builder.HasKey(pr => pr.CountryCode); 

     builder.HasMany(m => m.Cities).WithOne(i=> i.Country).HasForeignKey(m=> m.CountryCode); 
     builder.HasMany(m => m.States).WithOne(i => i.Country).HasForeignKey(m => m.CountryCode); 
    } 
} 

但是，我想動態地做這件事，因爲之後會映射所有模型。我能找到nopCommerce的上下文類的解決方案，他們這樣做的：

protected override void OnModelCreating(DbModelBuilder modelBuilder) 
    { 
     //dynamically load all configuration 
     //System.Type configType = typeof(LanguageMap); //any of your configuration classes here 
     //var typesToRegister = Assembly.GetAssembly(configType).GetTypes() 

     var typesToRegister = Assembly.GetExecutingAssembly().GetTypes() 
     .Where(type => !String.IsNullOrEmpty(type.Namespace)) 
     .Where(type => type.BaseType != null && type.BaseType.IsGenericType && 
      type.BaseType.GetGenericTypeDefinition() == typeof(NopEntityTypeConfiguration<>)); 
     foreach (var type in typesToRegister) 
     { 
      dynamic configurationInstance = Activator.CreateInstance(type); 
      modelBuilder.Configurations.Add(configurationInstance); 
     } 
     //...or do it manually below. For example, 
     //modelBuilder.Configurations.Add(new LanguageMap()); 



     base.OnModelCreating(modelBuilder); 
    } 

我試圖實現這一點，我得到了一個錯誤：

protected override void OnModelCreating(ModelBuilder builder) 
    { 
     // TODO: Use Dynamic mapping by getting classes which uses QuantumEntityTypeConfiguration 
     var typesToRegister = Assembly.GetExecutingAssembly().GetTypes() 
     .Where(type => !String.IsNullOrEmpty(type.Namespace)) 
     .Where(type => type.BaseType != null && type.BaseType.IsGenericType && 
      type.BaseType.GetGenericTypeDefinition() == typeof(QuantumEntityTypeConfiguration<>)); 
     foreach (var type in typesToRegister) 
     { 
      dynamic configurationInstance = Activator.CreateInstance(type);     
      builder.Configurations.Add(configurationInstance); //Error in this line specifying:ModelBuilder has no defination for Configuration. 
     }} 

錯誤

那麼nopCommerce使用命名空間中的DbModelBuilder：System.Data.Entity和我使用模型構建器名稱空間下：Microsoft.EntityFrameworkCore。

因此，如果您有任何解決方案或建議。請告訴我。

Answer 1

在EF Core中，沒有Configurations屬性可用於ModeBuilderas of now。要解決此問題

的一種方法是改變你的配置，以

public class CountryMap : QuantumEntityTypeConfiguration<Country> 
{ 
    public CountryMap(ModelBuilder modelBuilder) 
    { 
     EntityTypeBuilder<Country> builder = modelBuilder.Entity<Country>() 

     builder.ToTable("Country"); 
     builder.HasKey(pr => pr.CountryCode); 

     builder.HasMany(m => m.Cities).WithOne(i=> i.Country).HasForeignKey(m=> m.CountryCode); 
     builder.HasMany(m => m.States).WithOne(i => i.Country).HasForeignKey(m => m.CountryCode); 
    } 
} 

然後你就可以在OnModelCreating方法，這樣在你的DbContext的添加它們：

foreach (var type in typesToRegister) 
{  
    Activator.CreateInstance(type, modelBuilder); 
}