百度地图api 怎么返回驾车时间？

Question

代码如下：
function DrivingTime() {
var output = null; var time;
var searchComplete = function (results) {
if (transit.getStatus() != BMAP_STATUS_SUCCESS) {
return;
}
var plan = results.getPlan(0);
output = plan.getDuration(true);
}
var transit = new BMap.DrivingRoute(map, {
renderOptions: { map: map },
onSearchComplete: searchComplete,
onPolylinesSet: function () {
setTimeout(function () { time = output }, "1000");
}
});
transit.search("上地", "西单");
return time; //time=驾车的时间
}

各位大神,怎么让返回的time=驾车时间阿???

Answer 1

驾车时间其实也是估算，按照市区道路每小时20km，公路60km，高速每小时100km算下