如何使用php计算两个地方之间的距离？

Question

I want to display distance between hotel and user. For calculation Distance between hotel and user address I have used following code. Distance value I have get on button click.

1) First I have getting use IP address and get all user address information from IP address.

$ipAddress  = $_SERVER['REMOTE_ADDR'];
$result = json_decode(file_get_contents("http://ip-api.com/json/{$ipAddress}"));

This call give me details like city, country, countryCode, latitude, longitude, zip etc. Save latitude and longitude.

$user_latitude = $result->lat;
$user_longitude = $result->lon;

2) I have hotel latitude and longitude in our database already.

now I have four value. User latitude/longitude and Hotel latitude/longitude
$lat1   =   $user_latitude;
$long1  =   $user_longitude;
$lat2   =   $hotel_latitude;
$long2  =   $hotel_longitude;

3) After that with the use of google map API I have get full address of both (User and Hotel)

$url = "http://maps.googleapis.com/maps/api/geocode/json?latlng={$lat1},{$long1}&sensor=true";
$url2 = "http://maps.googleapis.com/maps/api/geocode/json?latlng={$lat2},{$long2}&sensor=true";

# Get address of User
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_PROXYPORT, 3128);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
$response = curl_exec($ch);
curl_close($ch);
$response_a = json_decode($response, true);
$address1 = $response_a['results'][0]['formatted_address'];

# Get address of Hotel
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url2);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_PROXYPORT, 3128);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
$response = curl_exec($ch);
curl_close($ch);
$response_a = json_decode($response, true);
$address2 = $response_a['results'][0]['formatted_address'];

$find = array("'",'"');
$replace = array("","");
$address1 = str_replace($find,$replace,$address1);
$address2 = str_replace($find,$replace,$address2);

4) At last I have use distance matrix API of google and get distance between two points.

$url = "https://maps.googleapis.com/maps/api/distancematrix/json?origins=".$lat1.",".$long1."&destinations=".$lat2.",".$long2."&alternatives=true&mode=driving&language=de-DE&sensor=false";

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_PROXYPORT, 3128);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
$response = curl_exec($ch);
curl_close($ch);
$response_a = json_decode($response, true);

$distance = $response_a['rows'][0]['elements'][0]['distance']['text'];
$time = $response_a['rows'][0]['elements'][0]['duration']['text'];

5) Distance is save in $distance and total time save in $time. It also give other details which you view in $response_a . Print the value of $response_a .

But all time it give me incorrect distance.

Answer 1

This stackoverflow thread has several implementations of the Haversine formula , which is used for distance calculation. In that thread, a PHP implementation is included as well, which I blatantly copied and pasted below.

<?php function distance($lat1, $lon1, $lat2, $lon2) {

    $pi80 = M_PI / 180;
    $lat1 *= $pi80;
    $lon1 *= $pi80;
    $lat2 *= $pi80;
    $lon2 *= $pi80;

    $r = 6372.797; // mean radius of Earth in km
    $dlat = $lat2 - $lat1;
    $dlon = $lon2 - $lon1;
    $a = sin($dlat / 2) * sin($dlat / 2) + cos($lat1) * cos($lat2) * sin($dlon / 2) * sin($dlon / 2);
    $c = 2 * atan2(sqrt($a), sqrt(1 - $a));
    $km = $r * $c;

    //echo '<br/>'.$km;
    return $km;
}
?>  

All credits go to the guy who posted the implementation in the thread linked above.

Answer 2

如果你希望两个点之间的距离，你可以使用那个 ，但是如果你想要一个行程的距离，你可能想使用谷歌地图API或某些等效。