6

我一直在使用 Google 的 DistanceMatrixService。下面的代码有效，但是，如何将另一个参数传递给回调函数或从回调中获取其中一个值？

例如：我有两个 div，我想在（Results1 和 Results2）中显示不同的结果，所以我想我需要
将另一个值传递给 GoogleMapDistance 函数，例如GoogleMapDistance(YourLatLong,DestLatLong,TheDiv)
或者
能够抓取回调外部的 ResultStr document.getElementById("Results1").innerHTML = ResultStr;
或者
将innerHTM设置为函数document.getElementById("Results1").innerHTML = GoogleMapDistance(YourLatLong,DestLatLong)的返回值；

我被困住了。我怎样才能做到这一点？它现在的样子是我只能运行一次所有这些代码，并且只写入一个 div。

<div id="Results1"></div>
<div id="Results2"></div>

<script src="https://maps.googleapis.com/maps/api/js?v=3.exp&sensor=false"></script>
<script>

function GoogleMapDistance(YourLatLong,DestLatLong)
{
    var service = new google.maps.DistanceMatrixService();
    service.getDistanceMatrix(
    {
    origins: [YourLatLong],
    destinations: [DestLatLong],
    travelMode: google.maps.TravelMode.DRIVING,
    unitSystem: google.maps.UnitSystem.IMPERIAL,
    avoidHighways: false,
    avoidTolls: false
    }, callback);
}

function callback(response, status)
{
    if (status == google.maps.DistanceMatrixStatus.OK)
    {
    var origins = response.originAddresses;
    var destinations = response.destinationAddresses;
      for (var i = 0; i < origins.length; i++)
      {
          var results = response.rows[i].elements;
          for (var j = 0; j < results.length; j++)
          {
              var element = results[j];
              var from = origins[i];
              var to = destinations[j];
              var distance = element.distance.text;
              var duration = element.duration.text;
              var ResultStr = distance + "&nbsp; (<i>" + duration + "</i>)";
          }
      }
    document.getElementById("Results1").innerHTML = ResultStr;
    }
}

var YourLatLong = "45.4049,-122.797997";
var DestLatLong1 = "47.468893,-122.227978";
var DestLatLong2 = "61.221274,-149.831545";

GoogleMapDistance(YourLatLong,DestLatLong1);

</script>
4

1 回答 1

11

您无法更改 Google 调用回调的方式，但您可以让它调用您自己的本地函数作为回调，然后在添加所需的额外参数后让它（通过闭包）调用另一个回调，如下所示：

function GoogleMapDistance(YourLatLong,DestLatLong, item)
{
    var service = new google.maps.DistanceMatrixService();
    service.getDistanceMatrix(
    {
    origins: [YourLatLong],
    destinations: [DestLatLong],
    travelMode: google.maps.TravelMode.DRIVING,
    unitSystem: google.maps.UnitSystem.IMPERIAL,
    avoidHighways: false,
    avoidTolls: false
    }, function(response, status) {callback(response, status, item)});
}

或者，您可以只定义您的回调内联，以便它可以直接访问父函数变量：

function GoogleMapDistance(YourLatLong,DestLatLong, item)
{
    var service = new google.maps.DistanceMatrixService();
    service.getDistanceMatrix(
    {
    origins: [YourLatLong],
    destinations: [DestLatLong],
    travelMode: google.maps.TravelMode.DRIVING,
    unitSystem: google.maps.UnitSystem.IMPERIAL,
    avoidHighways: false,
    avoidTolls: false
    }, function callback(response, status)
    {
        // you can access the parent scope arguments like item here
        if (status == google.maps.DistanceMatrixStatus.OK)
        {
        var origins = response.originAddresses;
        var destinations = response.destinationAddresses;
          for (var i = 0; i < origins.length; i++)
          {
              var results = response.rows[i].elements;
              for (var j = 0; j < results.length; j++)
              {
                  var element = results[j];
                  var from = origins[i];
                  var to = destinations[j];
                  var distance = element.distance.text;
                  var duration = element.duration.text;
                  var ResultStr = distance + "&nbsp; (<i>" + duration + "</i>)";
              }
          }
        document.getElementById("Results1").innerHTML = ResultStr;
        }
    }

)}
于 2012-12-27T22:29:54.327 回答