how return a distance in dbgeography to km?

Question

this is the json result of calculate distance from current position to another placess in the list but i have a issue i can't convert distance unit (degree) to km from dbgeography.location.distance this is my code :

 string CurrentLocation = String.Format("POINT(" + CurrentLat + " " + CurrentLng + ")", 4326);
                DbGeography point = DbGeography.PointFromText(CurrentLocation, DbGeography.DefaultCoordinateSystemId);

                var places = (from u in context.schoolinfo

                              orderby u.Location.Distance(point.Buffer(dist))

                              select u).Take(10).Select(x => new schoollinfo() { Name = x.name, Lat = x.Location.Latitude, Lng = x.Location.Longitude, Distance = x.Location.Distance(point.Buffer(dist)) }); ;

                var nearschools = places.ToList();
                return Json(nearschools, JsonRequestBehavior.AllowGet);

Print screen of result

Answer 1

为了计算距离，它是点（经度纬度）而不是点（纬度经度）所以代码将更改为：

     select u).Take(10).Select(x => new schoollinfo() { Name = x.name, Lat = x.Location.Latitude, Lng = x.Location.Longitude, Distance = DbGeography.FromText("POINT(" + x.Location.Longitude + " " + x.Location.Latitude + ")", 4326).Distance(point) });