How to store polygon coordinates in leaflet?

Question

JavaScript

How to get the coordinates of created polygons in a format like [-145.59082, 81.56997],[-149.80957, 81.4988],[-150.60059, 82.46607],[-146.25, 82.50629]?
or convert from format like "M253 207L450 290L684 178z"

Answer 1

polygons are created as objects and can be exported to GeoJSON

var polygon = L.polygon([
  [51.509, -0.08],
  [51.503, -0.06],
  [51.51, -0.047]
]).addTo(mymap);
JSON.stringify(polygon.toGeoJSON().geometry.coordinates[0]) 
""

You can unload all vector objects in general - like this:

var a = [];
mymap.eachLayer(l=>'toGeoJSON' in l && a.push(l.toGeoJSON()));
var result = {"type":"FeatureCollection","features":a};
console.log(JSON.stringify(result,"\n",4))