如何从Leaflet中的标记获取地图框坐标？

Question

I have a static map and markers (without the ability to zoom and move). I need that each marker check the four points where the map ends.

Any idea?

Answer 1

What you need are called the map bounds. The boundaries of the map. If you need those you can use the getBounds method of your L.Map instance which returns a L.LatLngBounds object:

var bounds = map.getBounds();

You can use that object to get the coordinates of the corners of your map:

var northWest = bounds.getNorthWest(),
    northEast = bounds.getNorthEast(),
    southWest = bounds.getSouthWest(),
    southEast = bounds.getSouthEast();

These methods return L.LatLng objects which contain the coordinates of those points:

northWest.lat // contains latitude of northwestern point
northWest.lng // contains longitude of northwestern point

I'm unsure as to why you would want to let each marker check the bounds since you stated that the map is static, which means every marker would return the same results. You could check the bounds once and use the results with all the markers.

Reference:

L.Map.getBounds(): http://leafletjs.com/reference.html#map-getbounds

L.LatLngBounds: http://leafletjs.com/reference.html#latlngbounds

L.LatLng: http://leafletjs.com/reference.html#latlng