Javascript 为什么不是'；t我的回调函数在使用Google距离矩阵服务API时被调用

以下代码工作正常，但未调用

回调

函数。

回调

功能中没有任何警报显示，但同时显示

开始

和

结束

警报。我已经检查了控制台，Google返回了您期望的数据，示例如下

我关心的是,

• 谷歌回复（

  /**/\uxdc.\u6ct5vb&&uxdc.\u6ct5vb（

  ）之前的奇怪代码是什么

• 当包含Google javascript文件时，URL参数callback=initMap在做什么

谷歌回应：

/**/_xdc_._6ct5vb && _xdc_._6ct5vb( {
   "destination_addresses" : [ "Church Rd, Liverpool L36 9TJ, UK" ],
   "origin_addresses" : [ "Ashfield Rd, Liverpool L17 0BZ, UK" ],
   "rows" : [
      {
         "elements" : [
            {
               "distance" : {
                  "text" : "5.1 mi",
                  "value" : 8175
               },
               "duration" : {
                  "text" : "16 mins",
                  "value" : 959
               },
               "status" : "OK"
            }
         ]
      }
   ],
   "status" : "OK"
}
 )

Javascript/jQuery：

<script async defer src="https://maps.googleapis.com/maps/api/js?key=<?php echo GOOGLE_MAPS_API_KEY; ?>&callback=initMap" type="text/javascript"></script><!-- Google Maps -->

  <script>
$( document ).ready(function() {

// validate form
$( "#add_employee_mileage" ).validate({
errorClass: "error-class"
});

$( "#calculateMileage" ).click(function() {

alert('Start');

var origin = $( "#employee_mileage_start_postcode" ).val();
var destination = $( "#employee_mileage_end_postcode" ).val();

var service = new google.maps.DistanceMatrixService();

service.getDistanceMatrix(
    {
        origins: [origin],
        destinations: [destination],
        travelMode: google.maps.TravelMode.DRIVING,
        unitSystem: google.maps.UnitSystem.IMPERIAL,
        avoidHighways: false,
        avoidTolls: false
    }, 
    callback
);

function callback(response, status) {

    alert('Callback');

    if(status=="OK") {
        alert('Ok');
        alert(response.rows[0].elements[0].distance.value);
        $( "#employee_mileage_mileage" ).val(response.rows[0].elements[0].distance.value);
    } else {
        alert("Error: " + status);
    }

}

alert('End');

});

});
</script>

---

以下代码适用于我。请注意，没有
回调
函数

  <script>
$( document ).ready(function() {

// validate form
$( "#add_employee_mileage" ).validate({
errorClass: "error-class"
});

$( "#calculateMileage" ).click(function() {

var origin_postcode = $( "#employee_mileage_start_postcode" ).val();
var destination_postcode = $( "#employee_mileage_end_postcode" ).val();

var distanceService = new google.maps.DistanceMatrixService();
    distanceService.getDistanceMatrix({
        origins: [origin_postcode],
        destinations: [destination_postcode],
        travelMode: google.maps.TravelMode.DRIVING,
        unitSystem: google.maps.UnitSystem.IMPERIAL,
        avoidHighways: false,
        avoidTolls: false
    },
    function (response, status) {
        if (status !== google.maps.DistanceMatrixStatus.OK) {
            alert('Error: ', status);
        } else {
            $( "#employee_mileage_mileage" ).val((response.rows[0].elements[0].distance.value * 0.000621371).toFixed(2));
        }
    });

 });

});
</script>


$（文档）.ready（函数（）{
//验证表单
$（“添加员工里程”）。验证({
errorClass:“错误类”
});
$（“#calculateMileage”）。单击（函数（）{
var origin_postcode=$（“#员工_里程_开始_postcode”）.val（）；
var destination_postcode=$（“#员工_里程_end_postcode”）.val（）；
var distanceService=new google.maps.DistanceMatrixService（）；
distanceService.getDistanceMatrix({
来源：[来源地\邮政编码]，
目的地：[目的地\邮政编码]，
travelMode:google.maps.travelMode.DRIVING，
unitSystem:google.maps.unitSystem.IMPERIAL，
避免：错误，
避免收费：错误
},
功能（响应、状态）{
if（status！==google.maps.DistanceMatrixStatus.OK）{
警报（'错误：'，状态）；
}否则{
$（“#员工_里程_里程”）.val（（response.rows[0]。elements[0]。distance.value*0.000621371）。toFixed（2））；
}
});
});
});
我没有地图。你为什么要添加地图？没有理由。你为什么不发布任何HTML？地图不应该是相关的。@geocodezip-对不起，这并不意味着你在没有地图的情况下就可以做小提琴了？
  <script>
$( document ).ready(function() {

// validate form
$( "#add_employee_mileage" ).validate({
errorClass: "error-class"
});

$( "#calculateMileage" ).click(function() {

var origin_postcode = $( "#employee_mileage_start_postcode" ).val();
var destination_postcode = $( "#employee_mileage_end_postcode" ).val();

var distanceService = new google.maps.DistanceMatrixService();
    distanceService.getDistanceMatrix({
        origins: [origin_postcode],
        destinations: [destination_postcode],
        travelMode: google.maps.TravelMode.DRIVING,
        unitSystem: google.maps.UnitSystem.IMPERIAL,
        avoidHighways: false,
        avoidTolls: false
    },
    function (response, status) {
        if (status !== google.maps.DistanceMatrixStatus.OK) {
            alert('Error: ', status);
        } else {
            $( "#employee_mileage_mileage" ).val((response.rows[0].elements[0].distance.value * 0.000621371).toFixed(2));
        }
    });

 });

});
</script>