//將角度轉爲狐度
$radLat1=deg2rad($lat1);//deg2rad()函數將角度轉換爲弧度
$radLat2=deg2rad($lat2);
$radLng1=deg2rad($lng1);
$radLng2=deg2rad($lng2);
$a=$radLat1-$radLat2;
$b=$radLng1-$radLng2;
$s=2*asin(sqrt(pow(sin($a/2),2)+cos($radLat1)*cos($radLat2)*pow(sin($b/2),2)))*6378.137*1000;
return $s;
}
(驗證結果地址:https://lbs.amap.com/api/javascript-api/example/calcutation/calculate-distance-between-two-markers)