How can I get city name from a latitude and longitude point?
Is there a way to get a city name from a latitude and longitude point using the google maps api for javascript?
If so could I please see a开发者_如何学Gon example?
This is called Reverse Geocoding
Documentation from Google:
http://code.google.com/apis/maps/documentation/geocoding/#ReverseGeocoding.
Sample Call to Google's geocode Web Service:
http://maps.googleapis.com/maps/api/geocode/json?latlng=40.714224,-73.961452&sensor=true&key=YOUR_KEY
Here is a complete sample:
<!DOCTYPE html>
<html>
<head>
<title>Geolocation API with Google Maps API</title>
<meta charset="UTF-8" />
</head>
<body>
<script>
function displayLocation(latitude,longitude){
var request = new XMLHttpRequest();
var method = 'GET';
var url = 'http://maps.googleapis.com/maps/api/geocode/json?latlng='+latitude+','+longitude+'&sensor=true';
var async = true;
request.open(method, url, async);
request.onreadystatechange = function(){
if(request.readyState == 4 && request.status == 200){
var data = JSON.parse(request.responseText);
var address = data.results[0];
document.write(address.formatted_address);
}
};
request.send();
};
var successCallback = function(position){
var x = position.coords.latitude;
var y = position.coords.longitude;
displayLocation(x,y);
};
var errorCallback = function(error){
var errorMessage = 'Unknown error';
switch(error.code) {
case 1:
errorMessage = 'Permission denied';
break;
case 2:
errorMessage = 'Position unavailable';
break;
case 3:
errorMessage = 'Timeout';
break;
}
document.write(errorMessage);
};
var options = {
enableHighAccuracy: true,
timeout: 1000,
maximumAge: 0
};
navigator.geolocation.getCurrentPosition(successCallback,errorCallback,options);
</script>
</body>
</html>
In node.js we can use node-geocoder npm module to get address from lat, lng.,
geo.js
var NodeGeocoder = require('node-geocoder');
var options = {
provider: 'google',
httpAdapter: 'https', // Default
apiKey: ' ', // for Mapquest, OpenCage, Google Premier
formatter: 'json' // 'gpx', 'string', ...
};
var geocoder = NodeGeocoder(options);
geocoder.reverse({lat:28.5967439, lon:77.3285038}, function(err, res) {
console.log(res);
});
output:
node geo.js
[ { formattedAddress: 'C-85B, C Block, Sector 8, Noida, Uttar Pradesh 201301, India',
latitude: 28.5967439,
longitude: 77.3285038,
extra:
{ googlePlaceId: 'ChIJkTdx9vzkDDkRx6LVvtz1Rhk',
confidence: 1,
premise: 'C-85B',
subpremise: null,
neighborhood: 'C Block',
establishment: null },
administrativeLevels:
{ level2long: 'Gautam Buddh Nagar',
level2short: 'Gautam Buddh Nagar',
level1long: 'Uttar Pradesh',
level1short: 'UP' },
city: 'Noida',
country: 'India',
countryCode: 'IN',
zipcode: '201301',
provider: 'google' } ]
Here is the latest sample of Google's geocode Web Service
https://maps.googleapis.com/maps/api/geocode/json?latlng=40.714224,-73.961452&key=YOUR_API_KEY
Simply change the YOUR_API_KEY to the API key you get from Google Geocoding API
P/S: Geocoding API is under Places NOT Maps ;)
Following Code Works Fine to Get City Name (Using Google Map Geo API) :
HTML
<p><button onclick="getLocation()">Get My Location</button></p>
<p id="demo"></p>
<script src="http://maps.google.com/maps/api/js?key=YOUR_API_KEY"></script>
SCRIPT
var x=document.getElementById("demo");
function getLocation(){
if (navigator.geolocation){
navigator.geolocation.getCurrentPosition(showPosition,showError);
}
else{
x.innerHTML="Geolocation is not supported by this browser.";
}
}
function showPosition(position){
lat=position.coords.latitude;
lon=position.coords.longitude;
displayLocation(lat,lon);
}
function showError(error){
switch(error.code){
case error.PERMISSION_DENIED:
x.innerHTML="User denied the request for Geolocation."
break;
case error.POSITION_UNAVAILABLE:
x.innerHTML="Location information is unavailable."
break;
case error.TIMEOUT:
x.innerHTML="The request to get user location timed out."
break;
case error.UNKNOWN_ERROR:
x.innerHTML="An unknown error occurred."
break;
}
}
function displayLocation(latitude,longitude){
var geocoder;
geocoder = new google.maps.Geocoder();
var latlng = new google.maps.LatLng(latitude, longitude);
geocoder.geocode(
{'latLng': latlng},
function(results, status) {
if (status == google.maps.GeocoderStatus.OK) {
if (results[0]) {
var add= results[0].formatted_address ;
var value=add.split(",");
count=value.length;
country=value[count-1];
state=value[count-2];
city=value[count-3];
x.innerHTML = "city name is: " + city;
}
else {
x.innerHTML = "address not found";
}
}
else {
x.innerHTML = "Geocoder failed due to: " + status;
}
}
);
}
BigDataCloud also has a nice API for this, also for nodejs users.
they have API for client - free. But also for backend, using API_KEY (free according to quota).
Their GitHub page.
the code looks like:
const client = require('@bigdatacloudapi/client')(API_KEY);
async foo() {
...
const location: string = await client.getReverseGeocode({
latitude:'32.101786566878445',
longitude: '34.858965073072056'
});
}
In case if you don't want to use google geocoding API than you can refer to few other Free APIs for the development purpose. for example i used [mapquest] API in order to get the location name.
you can fetch location name easily by implementing this following function
const fetchLocationName = async (lat,lng) => {
await fetch(
'https://www.mapquestapi.com/geocoding/v1/reverse?key=API-Key&location='+lat+'%2C'+lng+'&outFormat=json&thumbMaps=false',
)
.then((response) => response.json())
.then((responseJson) => {
console.log(
'ADDRESS GEOCODE is BACK!! => ' + JSON.stringify(responseJson),
);
});
};Here's a modern solution using a promise:
function getAddress (latitude, longitude) {
return new Promise(function (resolve, reject) {
var request = new XMLHttpRequest();
var method = 'GET';
var url = 'http://maps.googleapis.com/maps/api/geocode/json?latlng=' + latitude + ',' + longitude + '&sensor=true';
var async = true;
request.open(method, url, async);
request.onreadystatechange = function () {
if (request.readyState == 4) {
if (request.status == 200) {
var data = JSON.parse(request.responseText);
var address = data.results[0];
resolve(address);
}
else {
reject(request.status);
}
}
};
request.send();
});
};
And call it like this:
getAddress(lat, lon).then(console.log).catch(console.error);
The promise returns the address object in 'then' or the error status code in 'catch'
Following Code Works Fine For Me to Get City, state, country, zipcode (Using Google Map Geo API) :
var url = "https://maps.googleapis.com/maps/api/geocode/json?latlng="+lat+","+long+"&key=KEY_HERE&sensor=false";
$.get(url, function(data) {
var results = data.results;
if (data.status === 'OK')
{
//console.log(JSON.stringify(results));
if (results[0])
{
var city = "";
var state = "";
var country = "";
var zipcode = "";
var address_components = results[0].address_components;
for (var i = 0; i < address_components.length; i++)
{
if (address_components[i].types[0] === "administrative_area_level_1" && address_components[i].types[1] === "political") {
state = address_components[i].long_name;
}
if (address_components[i].types[0] === "locality" && address_components[i].types[1] === "political" ) {
city = address_components[i].long_name;
}
if (address_components[i].types[0] === "postal_code" && zipcode == "") {
zipcode = address_components[i].long_name;
}
if (address_components[i].types[0] === "country") {
country = address_components[i].long_name;
}
}
var address = {
"city": city,
"state": state,
"country": country,
"zipcode": zipcode,
};
console.log(address);
}
else
{
window.alert('No results found');
}
}
else
{
window.alert('Geocoder failed due to: ' + status);
}
});
Same as @Sanchit Gupta.
in this part
if (results[0]) {
var add= results[0].formatted_address ;
var value=add.split(",");
count=value.length;
country=value[count-1];
state=value[count-2];
city=value[count-3];
x.innerHTML = "city name is: " + city;
}
just console the results array
if (results[0]) {
console.log(results[0]);
// choose from console whatever you need.
var city = results[0].address_components[3].short_name;
x.innerHTML = "city name is: " + city;
}
There are many tools available
- google maps API as like all had written
- use this data "https://simplemaps.com/data/world-cities" download free version and convert excel to JSON with some online converter like "http://beautifytools.com/excel-to-json-converter.php"
- use IP address which is not good because using IP address of someone may not good users think that you can hack them.
other free and paid tools are available also
public function retornaCidade ( $lat, $lng )
{
$key = "SUA CHAVE";
$url = 'https://maps.googleapis.com/maps/api/geocode/json?latlng=' . $lat . ',' . $lng . '&key=' . $key;
$geoFull = json_decode ( file_get_contents ( $url ), true );
if ( $geoFull[ 'results' ] )
{
//console.log(JSON.stringify(results));
if ( $geoFull[ 'results' ][ 0 ] )
{
$cidade = "";
$estado = "";
$pais = "";
$cep = "";
$address_components = $geoFull[ 'results' ][ 0 ][ 'address_components' ];
for ( $i = 0; $i < count ( $address_components ); $i++ )
{
if ( ($address_components[ $i ][ 'types' ][ 0 ] == "administrative_area_level_1") && ($address_components[ $i ][ 'types' ][ 1 ] == "political" ))
{
$estado = str_replace('State of ', '',$address_components[ $i ][ 'long_name' ]);];
}
if ( ($address_components[ $i ][ 'types' ][ 0 ] == "administrative_area_level_2") && ($address_components[ $i ][ 'types' ][ 1 ] == "political" ))
{
$cidade = $address_components[ $i ][ 'long_name' ];
}
if ( $address_components[ $i ][ 'types' ][ 0 ] == "postal_code" && $cep == "" )
{
$cep = $address_components[ $i ][ 'long_name' ];
}
if ($address_components[ $i ][ 'types' ][ 0 ] == "country" )
{
$pais = $address_components[ $i ][ 'long_name' ];
}
}
$endereco = [
"cidade" => $cidade,
"estado" => $estado,
"pais" => $pais,
"cep" => $cep,
];
return $endereco;
}
else
{
return false;
}
}
else
{
return false;
}
}
You can use this library in your API based on Node to do reverse geocoding:
https://github.com/rapomon/geojson-places
you can do it with pure php and google geocode api
/*
*
* @param latlong (String) is Latitude and Longitude with , as separator for example "21.3724002,39.8016229"
**/
function getCityNameByLatitudeLongitude($latlong)
{
$APIKEY = "AIzaXXXXXXXXXXXXXXXXXXXXXXXXXXX"; // Replace this with your google maps api key
$googleMapsUrl = "https://maps.googleapis.com/maps/api/geocode/json?latlng=" . $latlong . "&language=ar&key=" . $APIKEY;
$response = file_get_contents($googleMapsUrl);
$response = json_decode($response, true);
$results = $response["results"];
$addressComponents = $results[0]["address_components"];
$cityName = "";
foreach ($addressComponents as $component) {
// echo $component;
$types = $component["types"];
if (in_array("locality", $types) && in_array("political", $types)) {
$cityName = $component["long_name"];
}
}
if ($cityName == "") {
echo "Failed to get CityName";
} else {
echo $cityName;
}
}
加载中,请稍侯......
精彩评论