Generic class map EntityBase <TEntity> with FluentNHibernate

I have a base class for all my entity types that is similar to

public abstract class EntityBase<TEntityType> : IEntityBase where TEntityType : EntityBase<TEntityType>
        private List<IBusinessRule> _brokenRules = new List<IBusinessRule>();

        private int? _hashCode;

        public int ID { private set; get; }


and in my mappings I would like to use the table per class strategy, but how do I map this class to EntityBase? I tried public class EntityBaseMap: ClassMap but it doesn't work. So how can I map this class? The reason I want this is, I don't want to write repeating things with Id(c=c.ID).Not.Null ....

, etc., but have it in the same mapping class.

my display class looks like this

public class EntityBaseMap : ClassMap<EntityBase<???>>


what should i insert instead of <



source to share

3 answers

In NHibernate, you cannot map a class to a public generic , eg EntityBase<TEntityType>

. Unfortunately, you will need to define a display class for each of the objects:

public class MyEntityMap : ClassMap<EntityBase<MyEntity>>




However, you can simplify the process through reflection by creating a generic mapping and then using runtime typing instead of creating static types:

    private static void AddWeakReferenceMappings(FluentMappingsContainer container, Assembly assembly)
        var genericMappingType = typeof (WeakReferenceMap<>);
        var entityTypes = assembly.GetTypes().Where(type => type.IsSubclassOf(typeof (Entity)));
        foreach (var enitityType in entityTypes)
            var newType = genericMappingType.MakeGenericType(enitityType);




As a workaround, you can define a non-generic Proxy class to be implemented EntityBaseMap


public abstract class EntityProxy:IEntityBase
  public virtual Int Id {get; set;}
  /* Shared properties/ repetitive mappings */


And display with

public class EntityProxyMap : ClassMap<EntityProxy>
  /* Mapping*/


So, you can create EntityBase


public abstract class EntityBase<TEntityType> : EntityProxy where TEntityType : EntityBase<TEntityType>
  /* Your implementation */


And finally use

public class YourSubclassMap : SubclassMap<EntityBase<YourSubclass>>
  /* Do any necessary sub-class mapping */




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