给定以下模型:

using NetTopologySuite.Geometries;

public class bounding_box
{
    public virtual int id { get; protected set; }
    public virtual Polygon area { get; set; }
}


使用Fluent Nhibernate生成数据库模式时,如何将area属性自动映射到area geometry(Polygon)列?请注意,由于我将在代码中使用GDAL,因此我不关心能够使用NHibernate读取/更新几何列。

我知道我可以通过实现手动替代来做到这一点,即:

public class bounding_boxMappingOverrride : IAutoMappingOverride<bounding_box>
{
    public void Override(AutoMapping<bounding_box> mapping)
    {
        mapping.Map(x => x.area)
            .CustomSqlType("geometry(Polygon)");
    }
}


但是,我有许多带有几何列的表,因此我更希望能够指定自定义类型映射。

由于某些原因,以下属性约定永远不会拦截area属性:

public class PostgisTypesConvention : IPropertyConvention
{
    public void Apply(IPropertyInstance instance)
    {
        if (instance.Type == typeof(Polygon))
        {
            instance.CustomSqlType("geometry(Polygon)"); // Never reached
        }
    }
}


如果我使用GeoAPI.Geometries.IPolygon而不是NetTopologySuite.Geometries.Polygon,我也会遇到同样的问题...

最佳答案

我终于能够通过定义自定义UserTypeConvention来解决此问题,即:

using NetTopologySuite.Geometries;
using NHibernate.Spatial.Type;

public class PostGisPolygonUserTypeConvention : UserTypeConvention<PostGisGeometryType>
{
    public override void Accept(IAcceptanceCriteria<IPropertyInspector> criteria)
    {
        criteria.Expect(c => c.Type == typeof(Polygon));
    }

    public override void Apply(IPropertyInstance instance)
    {
        // Have to set CustomType to be able to read/write rows using NHibernate
        instance.CustomType<PostGisGeometryType>();
        // Have to set CustomSqlType to generate correct SQL schema
        instance.CustomSqlType("geometry(Polygon)");
    }
}


同样的原理也可以用于为其他几何(例如UserTypeConventionsPointLineString等)创建MultiPoint

07-24 09:37
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