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c#.netnhibernatenhibernate-mapping-by-code

NHibernate 3.2 By Code (Conformist) ClassMapping For a Dictionary Property


Assume I have a class "SomeClass" that has a lookup dictionary: DataDictionary;

I currently have a mapping in SomeClass.hbm.xml like this:

<class name="SomeClass>

  <id name="ID" type="System.Guid">
    <generator class="guid" />
  </id>

  <map name="DictionaryProperty" table="SomeClass_Data">
    <key column="SomeClassID" />
    <index column="Key" type="System.String" />
    <element column="Value" type="System.String" />
  </map>

</class>

I want to use NHibernate's new (version 3.2) By Code mappings. How would I map the dictionary property above?

Currently I have:

  public class SomeClassMap :ClassMap<SomeClass>
  {

     public SomeClassMap()
     {
        Id(x => x.ID, mapping => mapping.Generator(Generators.Guid));
        Map(x = x.DictionaryProperty, mapping =>
           {
              mapping.Key(k => k.Column("SomeClassID"));
              mapping.Table("SomeClassData");
           });
     }

  }

Mostly I am at a loss for how to specify the equivalent of the index and the element for a dictionary mapping.


Solution

  • Each part of the dictionary mapping requires a separate delegate:

    Map(x => x.DictionaryProperty,
        mapping =>
        {
            mapping.Key(k => k.Column("SomeClassID"));
            mapping.Table("SomeClassData");
        },
        mapping => mapping.Element(k => k.Column("Key")),
        mapping => mapping.Element(k => k.Column("Value")));
    

    The first Element is the map-key (index is obsolete for map), and the second one is the element.