Entity Framework Core Point conversion

Use Arc’s AsPoint() to store a Cratis.Geospatial.Point location as a plain JSON string in Entity Framework Core. Configure it explicitly; BaseDbContext does not call it automatically. If you need native spatial queries instead, choose a compatible provider mapping before creating the column.

Configure string conversion

Define the entity and context below, then register the context in your configured Arc host. This example derives from plain DbContext, so Arc’s automatic context discovery will not register it. The explicit registration follows the declarations; apply your database schema separately.

using Cratis.Arc.EntityFrameworkCore;
using Cratis.Geospatial;
using Microsoft.EntityFrameworkCore;

public class Store
{
    public int Id { get; set; }
    public required Point Location { get; set; }
}

public class StoreDbContext(DbContextOptions<StoreDbContext> options) : DbContext(options)
{
    public DbSet<Store> Stores => Set<Store>();

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Store>().Property(store => store.Location).AsPoint();
        base.OnModelCreating(modelBuilder);
    }
}

After declaring the context, add this startup fragment, where services is the host’s IServiceCollection:

using Cratis.Arc.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;

services.AddDbContextWithConnectionString<StoreDbContext>("Data Source=store.db");

AsPoint() takes no database argument. It uses plain System.Text.Json, not the GeoJSON format used for geographic data. For new Point(Longitude: -122.4194, Latitude: 37.7749), the converted value is:

{"Longitude":-122.4194,"Latitude":37.7749}

The converter does not validate coordinate ranges. Validate longitude/latitude in your application. EF normally handles a null property without passing it through the value converter; choose property and column nullability consistently.

Choose one storage path

Path	Configuration	Storage contract
String conversion	Explicit AsPoint(), AsLineString(), or AsPolygon()	Plain JSON string; SQL type comes from the EF string mapping or your explicit configuration
JSON property	[Json] with BaseDbContext or ApplyJsonConversion	JSON conversion options and provider-specific JSON column mapping; see JSON conversion
Spatial migration	AddPointColumn, AddLineStringColumn, AddPolygonColumn	Spatial SQL type declarations on PostgreSQL/SQL Server, text on SQLite; not a geometry value converter

Choose one conversion per property: do not apply both string and [Json] conversion. Their serializer options and stored formats are separate. Neither conversion alone provides SQL translation for distance, intersection, or nested-coordinate LINQ queries.

Migration usage

For a string-converted point, use an ordinary string column aligned with your model mapping. Arc has no PointColumn() helper for CreateTable. The separate MigrationBuilder.AddPointColumn method selects these types:

PostgreSQL	SQL Server	SQLite
geometry(Point, 4326)	geography	TEXT

AddPointColumn declares a column; it does not configure native spatial conversion. Arc provides no automatic adapter between its PostgreSQL/SQL Server spatial columns and AsPoint()’s JSON string. For native spatial storage, configure a compatible provider mapping and database prerequisites, such as PostGIS for PostgreSQL, then verify migrations and save/load behavior for your application.

See adding columns, LineString conversion, and Polygon conversion.