to load a geojson file in OL3 use :
var yourVectorSource=new ol.source.Vector({
projection : 'EPSG:3857',
url: 'yourFile.geojson',
format: new ol.format.GeoJSON()
});
for the source then set it to a vector layer
to load a geojson file in OL3 use :
var yourVectorSource=new ol.source.Vector({
projection : 'EPSG:3857',
url: 'yourFile.geojson',
format: new ol.format.GeoJSON()
});
for the source then set it to a vector layer