Geospatial Point Mapping in Fluent NHibernate - asp.net-mvc

Question

I'm struggling to get Fluent NHibernate to play nice with SQL Server's Geospatial types. I want to store a geographic point in my Place class, but I keep getting an NHibernate configuration error when I run my ASP.NET MVC app:
Method 'SetParameterValues' in type 'NHibernate.Spatial.Type.GeometryType' from
assembly 'NHibernate.Spatial, Version=1.0.0.0, Culture=neutral,
PublicKeyToken=null' does not have an implementation.
Update: This is caused by an out-dated NHibernate.Spatial DLL. Referencing the latest version (2.2+) solves the problem. Kudos to psousa for leading me to a solution.
Place class:
using System;
using GisSharpBlog.NetTopologySuite.Geometries;
using NHibernate.Validator.Constraints;
namespace MyApp.Data.Entities
{
public class Place
{
public virtual Guid Id { get; set; }
public virtual string Name { get; set; }
public virtual Point Location { get; set; }
}
}
Fluent Place Mapping:
using MyApp.Data.Entities;
using FluentNHibernate.Mapping;
using NHibernate.Spatial.Type;
namespace MyApp.Data.Mappings
{
public class PlaceMap : ClassMap<Place>
{
public PlaceMap()
{
ImportType<GisSharpBlog.NetTopologySuite.Geometries.Point>();
Id(x => x.Id);
Map(x => x.Name);
Map(x => x.Location)
.CustomType(typeof(GeometryType));
}
}
}
Fluent NHibernate Configuration:
var cfg = Fluently.Configure()
.Database(MsSqlConfiguration.MsSql2008
.ConnectionString(c => c.FromConnectionStringWithKey(connectionStringKey))
.ShowSql()
.Dialect("NHibernate.Spatial.Dialect.MsSql2008GeographyDialect,NHibernate.Spatial.MsSql2008"))
.ExposeConfiguration(BuildSchema)
.Mappings(x => x.FluentMappings.AddFromAssembly(typeof(UserMap).Assembly)
.Conventions.AddFromAssemblyOf<ColumnNullabilityConvention>());

Answer 1

You're using a Geography dialect but using a CustomType of Geometry on your mapping. You should use a custom type of Geography. Something like:
public class PlaceMap : ClassMap<Place>
{
public PlaceMap()
{
Id(x => x.Id);
Map(x => x.Name);
Map(x => x.Location).CustomType(typeof(MsSql2008GeographyType)); //for SQL2008
}
}
Also, there's something else that you may need to do. If your spatial column has an SRID different from 0 (zero), and if you want to skip NH xml mappings, you'll need to declare a custom type like this:
public class Wgs84GeographyType : MsSql2008GeographyType
{
protected override void SetDefaultSRID(GeoAPI.Geometries.IGeometry geometry)
{
geometry.SRID = 4326;
}
}
And then use it on your mapping:
public class PlaceMap : ClassMap<Place>
{
public PlaceMap()
{
Id(x => x.Id);
Map(x => x.Name);
Map(x => x.Location).CustomType(typeof(Wgs84GeographyType));
}
}
UPDATE:
You should be referencing NHibernate.Spatial.MsSql2008.dll, and I would advise you to use the strongly-typed Dialect method in your database configuration.
.Dialect<MsSql2008GeographyDialect>()