GeoJson规范.doc

The GeoJSON Format Specification Authors: Howard Butler (Hobu Inc.) Martin Daly (Cadcorp) Allan Doyle (MIT) Sean Gillies (UNC-Chapel Hill) Tim Schaub (OpenGeo) Christopher Schmidt (MetaCarta) Revision: 1.0 Date: 16 June 2008 Copyright: Copyright ? 2008 by the Authors. This work is licensed under a Creative Commons Attribution 3.0 United States License. Abstract GeoJSON is a geospatial data interchange format based on JavaScript Object Notation (JSON). Contents 1. Introduction 1.1. Examples 1.2. Definitions 2. GeoJSON Objects 2.1 Geometry Objects 2.1.1. Positions 2.1.2. Point 2.1.3. MultiPoint 2.1.4. LineString 2.1.5. MultiLineString 2.1.6. Polygon 2.1.7. MultiPolygon 2.1.8 Geometry Collection 2.2. Feature Objects 2.3. Feature Collection Objects 3. Coordinate Reference System Objects 3.1. Named CRS 3.2. Linked CRS 3.2.1. Link Objects 4. Bounding Boxes Appendix A. Geometry Examples Point LineString Polygon MultiPoint MultiLineString MultiPolygon GeometryCollection Appendix B. Contributors 1. Introduction GeoJSON is a format for encoding a variety of geographic data structures. A GeoJSON object may represent a geometry, a feature, or a collection of features. GeoJSON supports the following geometry types: Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, and GeometryCollection. Features in GeoJSON contain a geometry object and additional properties, and a feature collection represents a list of features. A complete GeoJSON data structure is always an object (in JSON terms). In GeoJSON, an object consists of a collection of name/value pairs -- also called members. For each member, the name is always a string. Member values are either a string, number, object, array or one of the literals: true, false, and null. An array consists of elements where each element is a value as described above. 1.1. Examples A GeoJSON feature collection: { type: FeatureCollection, features: [ { type: Feature, geometry: {type: Point, coordinate