JavaScript计算谷歌地图V3中两点之间的距离

如果要自己计算，可以使用Haversine公式：

var rad = function(x) {  return x * Math.PI / 180;};var getDistance = function(p1, p2) {  var R = 6378137; // Earth’s mean radius in meter  var dLat = rad(p2.lat() - p1.lat());  var dLong = rad(p2.lng() - p1.lng());  var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +    Math.cos(rad(p1.lat())) * Math.cos(rad(p2.lat())) *    Math.sin(dLong / 2) * Math.sin(dLong / 2);  var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));  var d = R * c;  return d; // returns the distance in meter};