javascript - Openlayers 3 : popup by geojson file -

how put geojson attribute information in popup openlayers 3

i need display informations included in geojson file popup. here method gives me undefined.

my geojson file:

{ "type": "featurecollection", "features": [{ "type": "feature", "properties": { "name": "caen - campus 3 "}, "geometry": { "type": "point", "coordinates": [-0.353538,49.148791] } }, { "type": "feature", "properties": { "name": "caen "}, "geometry": { "type": "point", "coordinates": [-0.369770,49.184403] } } 

here method

var element = document.getelementbyid('popup');  var popup = new ol.overlay({    element: element  });  map.addoverlay(popup)   map.on('click', function(evt){    var feature = map.foreachfeatureatpixel(evt.pixel,   function(feature, layer) {  return feature;   });    if ( feature ) { var geometry = feature.getgeometry(); var coord = geometry.getcoordinates();  var nom = feature.getproperties(); //var nam = nom.type; popup.setposition(coord); $(element).popover({   'placement': 'top',   'html': true,   'content': '<p>'+feature.get('name')+'</p>' }); $(element).popover('show');    } else { $(element).popover('destroy');   }  }); 

i create popup when click on displays me 'undefined'. think don't use method put 'name' object included on geojson file: feature.get('name')

i think don't uses best method. thank help.