entity-framework-4.1

问题 Is there a way to decorate your POCO classes to automatically eager-load child entities without having to use Include() every time you load them? Say I have a Class Car, with Complex-typed Properties for Wheels, Doors, Engine, Bumper, Windows, Exhaust, etc. And in my app I need to load my car from my DbContext 20 different places with different queries, etc. I don't want to have to specify that I want to include all of the properties every time I want to load my car. I want to say List<Car>

问题 I have a repositories implemented with unitOfWork pattern and share a context. i have a service layer on top of these repositories. which has multiple services. When ever i instantiate a service class - unitOfWork instance is created. But many times these services methods call each other and sometimes operate on common session objects. Which causes a problem of the same entity being tracked by multiple contexts or more specifically - An entity object cannot be referenced by multiple instances

问题 When Initializer.Seed() uses DbContext.DbSet.Find() to set the navigation properties for a new Proxy, it correctly assigns the FK's to the Proxy, but the first navigation property is always null when I break on SaveChanges() and inspect the Proxy. Does anyone know why it does this? (Sorry, I can't post a screenshot of the locals window.) Model public class Thing : Base { public virtual Nullable<int> Option1ID { get; set; } public virtual Option1 Option1 { get; set; } public virtual Nullable

问题 I'm trying to use MVC 3 with EF 4.1 using code first and am following Scott Guthries tutorial http://weblogs.asp.net/scottgu/archive/2011/05/05/ef-code-first-and-data-scaffolding-with-the-asp-net-mvc-3-tools-update.aspx. The issue I'm having is that when I create the products controller and the related scaffolded views, there is no "category" column being created in any of the views ("edit", "create", "index" etc), which according to the tutorial should be created. I've traced the reason why

问题 I have a DbContext with several of the following type of members: public DbSet<JobLevel> JobLevels { get; set; } public DbSet<Country> Countries { get; set; } public DbSet<Race> Races { get; set; } public DbSet<Language> Languages { get; set; } public DbSet<Title> Titles { get; set; } All these are where T: IdNamePairBase , which has Id and Name members only. I am trying desperately to find a common interface with which to access any of these members, to generalise the following MVC3

问题 I'm having an odd issue with EF 4.1 Code First where even though I have configured an entity to generate columns for its inherited properties, it still joins to the inherited type's table. Here are my classes: public class Human { public int Id { get; set; } public string Name { get; set; } } public class SuperHuman : Human { public int Id { get; set; } public string Powers { get; set; } } public class MarvelDbContext : DbContext { public DbSet<Human> Humans { get; set; } public DbSet

问题 I'm having an odd issue with EF 4.1 Code First where even though I have configured an entity to generate columns for its inherited properties, it still joins to the inherited type's table. Here are my classes: public class Human { public int Id { get; set; } public string Name { get; set; } } public class SuperHuman : Human { public int Id { get; set; } public string Powers { get; set; } } public class MarvelDbContext : DbContext { public DbSet<Human> Humans { get; set; } public DbSet

问题 I have two entities: Municipality and RoadSemgents. Municipality is parent and RoadSegments is a child table. I need to have two foreign Keys in RoadSegments from the same table (Municipality). public class Municipality { [Key] public int ID { get; set; } public string Name { get; set; } } public class RoadSegments { [Key] public int ID { get; set; } //ForeignKeys public int CodeMunicipalityLeft_ID { get; set; } public int CodeMunicipalityRight_ID { get; set; } [ForeignKey(

问题 I'm using Entity Framework 4.1 with MySql and having a problem with the eager loading of a many to many relationship. A simplified version of the affected tables looks like: CabinCategory - CabinCategoryId CabinGrade - CabinGradeId, CabinCategoryId Deck - DeckId DeckCabinGrades - DeckId, CabinGradeId <--- Join table I'm ultimately trying to access CabinCategory.CabinGrade.Deck I think I've managed to map this successfully using modelBuilder.Entity<CabinGrade>() .HasMany(c => c.Decks)

问题 I'm using Entity Framework 4.1 with MySql and having a problem with the eager loading of a many to many relationship. A simplified version of the affected tables looks like: CabinCategory - CabinCategoryId CabinGrade - CabinGradeId, CabinCategoryId Deck - DeckId DeckCabinGrades - DeckId, CabinGradeId <--- Join table I'm ultimately trying to access CabinCategory.CabinGrade.Deck I think I've managed to map this successfully using modelBuilder.Entity<CabinGrade>() .HasMany(c => c.Decks)