Javascript can't access global variables outside function

Question

I'm using google map geocoding to get latitude,longitude value from address.Here is my code,

var latd;
var lond;
geocoder.geocode({ 'address': address }, function (results, status) {

    if (status == google.maps.GeocoderStatus.OK) {
       console.log(place);
       var latd = results[0].geometry.location.lat();
       var lond = results[0].geometry.location.lng();
     }
    console.log(latd);
});
//console.log(latd);

When access the variable latd outside function, its value seems undefined. What's the issue with the above code?

Update1:

    getlatlang(address);
    console.log(latd);//Not defined


function getlatlang(address)
{
    var geocoder = new google.maps.Geocoder();
    geocoder.geocode({ 'address': address }, function (results, status) {

        if (status == google.maps.GeocoderStatus.OK) {
            //console.log(place);
            latd = results[0].geometry.location.lat();
            lond = results[0].geometry.location.lng();
             return latd,lond;
             }

     });
}

remove keyword 'var' from if condition. – Uttam Kukadiya Apr 12 '18 at 12:45 — Uttam Kukadiya, Apr 12 '18 at 12:45

Radonirina Maminiaina · Answer 1 · 2018-04-12T13:06:33.513

1

First, because the variable you try to access into your condition will be accessible only into the context if. The variable your redeclared into if is new variable.

if (status == google.maps.GeocoderStatus.OK) {
   console.log(place);
   var latd = results[0].geometry.location.lat();
   var lond = results[0].geometry.location.lng();
   console.log(latd, lond)
}

You can change with this:

var latd;
var lond;
geocoder.geocode({ 'address': address }, function (results, status) {

   if (status == google.maps.GeocoderStatus.OK) {
      console.log(place);
      latd = results[0].geometry.location.lat();
      lond = results[0].geometry.location.lng();
   }
   console.log(latd);
});

Update

geocoder.geocode is an async function. You have to wait until it's done. Your variable after the geocoder.geocod is executed even if the geocoder hasn't yet finished to be executed. So your variable is always undefined, because you create a variable with undefined value.

Note: All your action should be into the callback function, of geocoder, otherwise, it will always undefined.

edited Apr 12 '18 at 13:06

answered Apr 12 '18 at 12:43

Radonirina Maminiaina

6,958
4
33
60

With the above how can I access as `geocoder.geocode({ 'address': address }, function (results, status) { if (status == google.maps.GeocoderStatus.OK) { console.log(place); latd = results[0].geometry.location.lat(); lond = results[0].geometry.location.lng(); } }); console.log(latd);` like this – usertest Apr 12 '18 at 12:56
Updated my answer – Radonirina Maminiaina Apr 12 '18 at 13:06
Thanks.I got it! – usertest Apr 12 '18 at 13:08
All async functions work this way! – Radonirina Maminiaina Apr 12 '18 at 13:12
Updated my question – usertest Apr 12 '18 at 13:20

Denis Potapov · Answer 2 · 2018-04-12T12:55:53.113

1

If you want to have access to lat, long outside the function simply assign them and do not create them inside. You can read more about JavaScript Scope

    var latd;
    var lond;
     geocoder.geocode({ 'address': address }, function (results, status) {

        if (status == google.maps.GeocoderStatus.OK) {
            console.log(place);
            latd = results[0].geometry.location.lat();
            lond = results[0].geometry.location.lng();
         }
      console.log(latd);
     });
     //console.log(latd);

edited Apr 12 '18 at 12:55

answered Apr 12 '18 at 12:44

Denis Potapov

664
2
12
18

Thanks for your reply.I 've did it.But still it remains undefined when access from out of the function – usertest Apr 12 '18 at 12:52
Do you have a living example? Check whether condition `status == google.maps.GeocoderStatus.OK` is `true` – Denis Potapov Apr 12 '18 at 13:04

Javascript can't access global variables outside function

2 Answers2