Myujth

I want to use OpenLayers v5.3.0 to create a Web application.

I’m able to show all features from a external GeoJSON File as a Vector Layer above a OSM Layer, but my GeoJSON File holds thousands of features, each enriched by a lot of properties.

What I’m looking at is a way to be able to parse the GeoJSON File, filter it by properties (e.g. all features with the property "gender": "f", or "ethnic_gro": "Latvian",) and display only those as an additional Vector Layer above my OSM Base Layer.

This is an example of my GeoJSON File (abbriviated, with only one Feature):

 "type": "FeatureCollection",
 "features": [
 
 "type": "Feature",
 "geometry": 
 "type": "LineString",
 "coordinates": [
 [23.114870000000053, 56.845980000000134],
 [19.131050000000164, 50.65641000000013]
 ]
 ,
 "properties": 
 "OID_": "0",
 "ethnic_gro": "Latvian",
 "religion": "protestant",
 "marital_st": "widow",
 "status_in_": "NULL",
 "gender": "f",
 
 
 ]

Thanks for any help!

You could use a javascript array filter on the original features array to build a new GeoJSON object:

var filteredGeoJSON = 
 "type": "FeatureCollection",
 "features": fullGeoJSON.features.filter(function(feature)
 return (feature.properties.ethnic_gro == "Latvian" && feature.properties.gender == "f");
 )
;

or use a forEach loop to build a filtered array:

var filteredGeoJSON = 
 "type": "FeatureCollection",
 "features": 
;
fullGeoJSON.features.forEach(function(feature)
 if (feature.properties.ethnic_gro == "Latvian" && feature.properties.gender == "f") 
 filteredGeoJSON.features.push(feature);
 
);