retrieving lat/long of location using google.maps.geocoder

问题

i have been trying to use some ajax to save venue location in my application and stumbled across the following code on stack overflow

function getLatLong(address) 
{
    var geocoder = new google.maps.Geocoder();
    var result = "";
    geocoder.geocode( { 'address': address, 'region': 'uk' }, function(results, status) {
        if (status == google.maps.GeocoderStatus.OK) {
            result[lat] = results[0].geometry.location.Pa;
            result[lng] = results[0].geometry.location.Qa;
        } else {
            result = "Unable to find address: " + status;
        }
    });
    return result;
}

my problem is when i call the function it returns nothing and when i debug and set breakpoints in chrome it breaks on return result first before it breaks on the result[lat] = results[0].geometry.location.Pa;

I know the array should be declared as type array but even when i was just returning the results[0].geometry.location object nothing was being returned

what can i do to return the lat/long of the location so i can store in my db?

回答1:

The problem you're facing is that you're treating the geocoder.geocode function as immediately completing before you do the return result. What's really happening is that the geocoder.geocode is triggered, then you get an immediate return of result. Because the asynchronous result has most likely not returned, your result is empty. Think of the geocoding result as a push, not a pull. The storeResult function, not shown, is whatever code you need to do to save the information. Because you're combining a result with an error string, you have to handle that in your storeResult function. As an alternative, you can have a status in the result that indicates succcess or failure.

function getLatLong(address) {
var geocoder = new google.maps.Geocoder();
var result = "";
geocoder.geocode( { 'address': address, 'region': 'uk' }, function(results, status) {
     if (status == google.maps.GeocoderStatus.OK) {
         result[lat] = results[0].geometry.location.Pa;
         result[lng] = results[0].geometry.location.Qa;
     } else {
         result = "Unable to find address: " + status;
     }
     storeResult(result);
    });
}

回答2:

This is not the answer but don't use Pa and Qa always use the lng() and lat() functions:

 place.geometry.location
{...}
    Pa: 56.240477
    Qa: -0.902655999999979
    toString: function(){return"("+this.lat()+", "+this.lng()+")"}
    equals: function(a){return!a?k:Cd(this.lat(),a.lat())&&Cd(this.lng(),a.lng())}
    lat: function(){return this[a]}
    lng: function(){return this[a]}
    toUrlValue: function(a){a=Hd(a)?a:6;return $d(this.lat(),a)+","+$d(this.lng(),a)}

回答3:

I struggled hard with this and found the following to work.

Loop through the object and push into a new array:

var newArray = [];

for (var key in latLng) {

   newArray.push(key);

}

Call your object with variable values with the square bracket syntax, dot notation breaks:
```
var lat = latLng[newArray[0]];

var lng = latLng[newArray[1]];
```

回答4:

function getLatLong(address) 
{
    var geocoder = new google.maps.Geocoder();
    var result = '';
    geocoder.geocode( { 'address': address }, function(results, status{
        if (status == google.maps.GeocoderStatus.OK) {
            // Call the lat/lng functions to return a computed value.
            result[lat] = results[0].geometry.location.lat();
            result[lng] = results[0].geometry.location.lng();
        } else {
            result = 'Unable to find address: ' + status;
        }
    });
    return result;
}

getLatLong('address');

回答5:

In my case simplest solution for getting latitude and longitude from place object was:

  var latitude=place.geometry.location['k'];
  var longitude=place.geometry.location['A'];

来源：https://stackoverflow.com/questions/8807141/retrieving-lat-long-of-location-using-google-maps-geocoder

标签

javascript

jquery

google-maps-api-3

geocoding