OpenLayers

Class: GML

ol.format.GML

Feature format for reading and writing data in the GML format version 3.1.1. Currently only supports GML 3.1.1 Simple Features profile.

new ol.format.GML(opt_options)

src/ol/format/gml.js, line 18
Name Type Description
options

Optional configuration object.

Name Type Description
featureNS Object.<string, string> | string | undefined

Feature namespace. If not defined will be derived from GML. If multiple feature types have been configured which come from different feature namespaces, this will be an object with the keys being the prefixes used in the entries of featureType array. The values of the object will be the feature namespaces themselves. So for instance there might be a featureType item topp:states in the featureType array and then there will be a key topp in the featureNS object with value http://www.openplans.org/topp.
featureType Array.<string> | string | undefined

Feature type(s) to parse. If multiple feature types need to be configured which come from different feature namespaces, featureNS will be an object with the keys being the prefixes used in the entries of featureType array. The values of the object will be the feature namespaces themselves. So for instance there might be a featureType item topp:states and then there will be a key named topp in the featureNS object with value http://www.openplans.org/topp.
srsName string

srsName to use when writing geometries. Required.
surface boolean | undefined

Write gml:Surface instead of gml:Polygon elements. This also affects the elements in multi-part geometries. Default is false.
curve boolean | undefined

Write gml:Curve instead of gml:LineString elements. This also affects the elements in multi-part geometries. Default is false.
multiCurve boolean | undefined

Write gml:MultiCurve instead of gml:MultiLineString. Since the latter is deprecated in GML 3, the default is true.
multiSurface boolean | undefined

Write gml:multiSurface instead of gml:MultiPolygon. Since the latter is deprecated in GML 3, the default is true.
schemaLocation string | undefined

Optional schemaLocation to use when writing out the GML, this will override the default provided.

Extends

Methods

readFeatures(source, opt_options){Array.<ol.Feature>} inherited

src/ol/format/gmlbase.js, line 569

Read all features from a GML FeatureCollection.

Name Type Description
source Document | Node | Object | string

Source.
options

Options.

Name Type Description
dataProjection ol.ProjectionLike

Projection of the data we are reading. If not provided, the projection will be derived from the data (where possible) or the defaultDataProjection of the format is assigned (where set). If the projection can not be derived from the data and if no defaultDataProjection is set for a format, the features will not be reprojected.
featureProjection ol.ProjectionLike

Projection of the feature geometries created by the format reader. If not provided, features will be returned in the dataProjection.
Returns:
Features.

writeFeatures(features, opt_options){string}

src/ol/format/gml.js, line 30

Encode an array of features in GML 3.1.1 Simple Features.

Name Type Description
features Array.<ol.Feature>

Features.
options

Options.

Name Type Description
dataProjection ol.ProjectionLike

Projection of the data we are writing. If not provided, the defaultDataProjection of the format is assigned (where set). If no defaultDataProjection is set for a format, the features will be returned in the featureProjection.
featureProjection ol.ProjectionLike

Projection of the feature geometries that will be serialized by the format writer. If not provided, geometries are assumed to be in the dataProjection if that is set; in other words, they are not transformed.
rightHanded boolean | undefined

When writing geometries, follow the right-hand rule for linear ring orientation. This means that polygons will have counter-clockwise exterior rings and clockwise interior rings. By default, coordinates are serialized as they are provided at construction. If true, the right-hand rule will be applied. If false, the left-hand rule will be applied (clockwise for exterior and counter-clockwise for interior rings). Note that not all formats support this. The GeoJSON format does use this property when writing geometries.
decimals number | undefined

Maximum number of decimal places for coordinates. Coordinates are stored internally as floats, but floating-point arithmetic can create coordinates with a large number of decimal places, not generally wanted on output. Set a number here to round coordinates. Can also be used to ensure that coordinates read in can be written back out with the same number of decimals. Default is no rounding.
Returns:
Result.

writeFeaturesNode(features, opt_options){Node}

src/ol/format/gml.js, line 42

Encode an array of features in the GML 3.1.1 format as an XML node.

Name Type Description
features Array.<ol.Feature>

Features.
options

Options.

Name Type Description
dataProjection ol.ProjectionLike

Projection of the data we are writing. If not provided, the defaultDataProjection of the format is assigned (where set). If no defaultDataProjection is set for a format, the features will be returned in the featureProjection.
featureProjection ol.ProjectionLike

Projection of the feature geometries that will be serialized by the format writer. If not provided, geometries are assumed to be in the dataProjection if that is set; in other words, they are not transformed.
rightHanded boolean | undefined

When writing geometries, follow the right-hand rule for linear ring orientation. This means that polygons will have counter-clockwise exterior rings and clockwise interior rings. By default, coordinates are serialized as they are provided at construction. If true, the right-hand rule will be applied. If false, the left-hand rule will be applied (clockwise for exterior and counter-clockwise for interior rings). Note that not all formats support this. The GeoJSON format does use this property when writing geometries.
decimals number | undefined

Maximum number of decimal places for coordinates. Coordinates are stored internally as floats, but floating-point arithmetic can create coordinates with a large number of decimal places, not generally wanted on output. Set a number here to round coordinates. Can also be used to ensure that coordinates read in can be written back out with the same number of decimals. Default is no rounding.
Returns:
Node.