How To Get The Coordinates From The OpenLayers Map In ReactJS?

- 1 answer

Some three locations are connected in a triangle shape in Open Layer Map. I am trying to get all the three locations (latitude and longitude) with the help of OpenLayers and React JS. But unfortunately, I am able to get the Latitude and Longitude of visible view and not the marked layers.

When I used the below code, it is not fetching the expected long and lat and it is resulting the visible map long and lat.

var glbox = map.getView().calculateExtent(map.getSize()); 
var box = proj.transformExtent(glbox,'EPSG:3857','EPSG:4326'); 
console.log("Latitude and longitude :",box);

So, I have tried with the below options as well and it is not resulting the expected long and lat.

console.log("Long and Lat :",map.getFeaturesAtPixel());  //--> null
console.log("Long and Lat :",map.getLayers());  
console.log("Long and Lat :",map.getFeaturesAtPixel());  //--> null

How can I get the latitude and longitude of the all three locations that are shown in the image?

Map with Triangle Shape



It will never work the way you are currently doing things. What do I mean? I mean that going through map.getFeaturesAtPixel is one way that can work but you didn't read the API docs. You need at least to provide pixel (x, y screen coordinates) to the function.

You can get pixel using the following

map.on('click', evt => {

I've done a simple demo to illustrate. Go to and paste the following code in the browser debugger console. Click on point(s) and observe the behavior in the console.

map.on('click', evt => {
  var features = map.getFeaturesAtPixel(evt.pixel);
  if (features) {
    // Get name (but it depends of your data attributes)
      .filter(feature => feature.getGeometry().getType() == 'Point')
      .map(feature => feature.get('name')));
    // Get the features, filter to only get Point, then get geometry
    // and coordinates, change projection to lon lat
      .filter(feature => feature.getGeometry().getType() == 'Point')
      .map(feature => `Longitude, latitude: ${ol.proj.toLonLat(feature.getGeometry().getCoordinates()).join(', ')}`));

Edit due to feedback.

To get the points from a LineString, just do

var featuresLinestringPointsCoordinates = vector.getSource().getFeatures()
  .map(feature => {
    return feature
// More readable and we only get the first linestring

Tested on the official snap demo after drawing a LineString