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Note: Catfood.Shapefile.dll is not thread safe. You should open, enumerate and then close (dispose) a shapefile on the same thread. Jet drivers are used to access shapefile metadata.

To get started add a reference to Catfood.Shapefile.dll and import the {{Catfood.Shapefile}} namespace.

A shapefile consists of three files:

  • filename.shp - the main file containing shapes.
  • filename.shx - an index to the shapes in the main file.
  • filename.dbf - database containing metadata for each shape.

To enumerate shapes pass the path to any of these three files to the {{Shapefile}} constructor and then use the {{IEnumerable}} interface as demonstrated below:

{code:c#} using (Shapefile shapefile = new Shapefile("my.shp") { foreach (Shape shape in shapefile) { Console.WriteLine("ShapeType: {0}", shape.Type); } } {code:c#}

{{Shape}} is the base class for a set of more specific classes - {{ShapePoint}}, {{ShapeMultiPoint}}, {{ShapePolyLine}} and {{ShapePolygon}}. Cast to the appropriate class based on the {{Type}} property:

{code:c#} switch (shape.Type) { case ShapeType.Point: ShapePoint shapePoint = shape as ShapePoint; Console.WriteLine("Point={0},{1}", shapePoint.Point.X, shapePoint.Point.Y); break;

// ...

} {code:c#}

Access metadata for the shape using {{GetMetadataNames()}} to list available names (keys) and {{GetMetadata()}} to access metadata by name.

See the {{ShapefileDemo}} project for a sample command line application that dumps information for each shape in a shapefile.

Catfood.Shapefile uses the Jet driver to access shapefile metadata (stored in dBase format). The 32-bit version of this driver is almost certainly available on all systems. To use Catfood.Shapefile on 64-bit systems either target your application at x86 (it will then use the 32-bit Jet driver) or install the 64-bit Jet driver. From version 1.40 you can also change the default connection string template use to access shapefile metadata via a constructor overload. {{Shapefile.ConnectionStringTemplateJet}} is the default, {{Shapefile.ConnectionStringTemplateAce}} uses the ACE driver.

You may find it helpful to refer to the ERSI Shapefile Technical Description (PDF) for details about the properties of each shape type.