Using PHP (curl) to pull data from JSON (Google Maps API)
I'm fairly new to JSON, and I'm trying to get the latitude and longitude of a geocoded city from the Google Maps API using curl. The function I'm using is:
function geocode($city){
$cityclean = str_replace (" ", "+", $city);
$details_url = "http://maps.googleapis.com/maps/api/geocode/json?address=" . $cityclean . "&sensor=false";
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $details_url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$geoloc = json_decode(curl_exec($ch), true);
$step1 = $geoloc['results'];
$step2 = $step1['geometry'];
$coords = $step2['location'];
print $coords['lat'];
print $coords['lng'];
}
The goal of all of that is to pull the lat and lng values from the Results -> Geometry -> Location array of the following JSON:
{
"status": "OK",
"results": [ {
"types": [ "locality", "political" ],
"formatted_address": "Westminster, London, UK",
"address_components": [ {
"long_name": "London",
"short_name": "London",
"types": [ "locality", "political" ]
}, {
"long_name": "Westminster",
"short_name": "Westminster",
"types": [ "administrative_area_level_3", "political" ]
}, {
"long_name": "Greater London",
"short_name": "Greater London",
"types": [ "administrative_area_level_2", "political" ]
}, {
"long_name": "England",
"short_name": "England",
"types": [ "administrative_area_level_1", "political" ]
}, {
"long_name": "United Kingdom",
"short_name": "GB",
"types": [ "country", "political" ]
} ],
"geometry": {
"location": {
"lat": 51.5001524,
"lng": -0.1262362
},
"location_type": "APPROXIMATE",
"viewport": {
"southw开发者_如何转开发est": {
"lat": 51.3493528,
"lng": -0.3783580
},
"northeast": {
"lat": 51.7040647,
"lng": 0.1502295
}
},
"bounds": {
"southwest": {
"lat": 51.3493528,
"lng": -0.3783580
},
"northeast": {
"lat": 51.7040647,
"lng": 0.1502295
}
}
}
} ]
}
However, it doesn't print anything. I know that the function successfully retrieves the JSON from Google and brings it to my server, as I did a print statement for the 'status' value and it returned 'OK'. The problem seems to be when I try and delve deeper into the JSON.
Sorry if it's a straightforward problem, but like I said, I'm new to this and it's driving me crazy now.
Thanks a lot! :)
Note that it seems that results
contains an array (with only one item in it, here) of results ; and geometry
is one item inside one result.
Here, you can see that results' content is delimited by []
-- which indicates it's an array.
So, you have to first access the first result : $geoloc['results'][0]
Inside of which you'll have the geometry : $geoloc['results'][0]['geometry']
Which will allow you to get the latitude and longitude :
var_dump($geoloc['results'][0]['geometry']['location']['lat']);
var_dump($geoloc['results'][0]['geometry']['location']['lng']);
I suppose that, depending on the address you've searched on, you will sometimes have more than one item in the results
array.
You just need this :
$fullurl = "http://maps.googleapis.com/maps/api/geocode/json?address=1600+Amphitheatre+Parkway,+Mountain+View,+CA&sensor=true";
$string .= file_get_contents($fullurl); // get json content
$json_a = json_decode($string, true); //json decoder
echo $json_a['results'][0]['geometry']['location']['lat']; // get lat for json
echo $json_a['results'][0]['geometry']['location']['lng']; // get ing for json
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