php - 为什么我的脚本不断重新声明 php 函数？

Question

我有以下脚本，它基本上应该从我的 MySQL 表中获取字段，其中包括经度和纬度，并计算驾驶距离，然后将其作为列表回显给用户。

由于某种原因，脚本仅打印第一个结果，然后抛出错误 fatal error :无法重新声明 GetDrivingDistance()

mysqli_close($conn);            
$servername = "localhost";
$username = "user";
$password = "pwd";
$dbname = "buses";

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
     die("Connection failed: " . $conn->connect_error);
} 
$sql = "SELECT * 
                    FROM matatus 
                    JOIN registered_matatus
                    ON matatus.user_id=registered_matatus.user_id 
                    ORDER BY matatus.vehicle_id 
                    ASC LIMIT 4";
if ($result->num_rows > 0) {
     // output data of each row
     echo "CON Select a matatu\n";
     while($row = $result->fetch_assoc()) {
//Start of  calculate distance and time
$lat1 = "-1.283180";
$long1 = "36.822462";
$lat2 = $row["lat"];
$long2 = $row["lng"];

function GetDrivingDistance($lat1, $lat2, $long1, $long2)
{
    $url = "https://maps.googleapis.com/maps/api/distancematrix/json?origins=".$lat1.",".$long1."&destinations=".$lat2.",".$long2."&mode=driving&language=pl-PL";
    $ch = curl_init();
    curl_setopt($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);
    $dist = $response_a['rows'][0]['elements'][0]['distance']['text'];
    $time = $response_a['rows'][0]['elements'][0]['duration']['text'];
    return array('distance' => $dist, 'time' => $time);
}
    $dist = GetDrivingDistance($lat1, $lat2, $long1, $long2);
    $distance = $dist['distance'];
    $time = $dist['time'];
//End of calculate distance and time
         echo "". $row["id"]. " ". $row["reg_number"]. " (" . $row["sacco"] . ") -$time\n";
     }
} else {
     echo "0 results";
}
$conn->close();

任何关于如何解决这个问题的提示都将受到高度赞赏。

Answer 1

试试这个:
不能在循环中声明函数

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
     die("Connection failed: " . $conn->connect_error);
} 
$sql = "SELECT * 
                    FROM matatus 
                    JOIN registered_matatus
                    ON matatus.user_id=registered_matatus.user_id 
                    ORDER BY matatus.vehicle_id 
                    ASC LIMIT 4";
if ($result->num_rows > 0) {
     // output data of each row
     echo "CON Select a matatu\n";

function GetDrivingDistance($lat1, $lat2, $long1, $long2)
{
    $url = "https://maps.googleapis.com/maps/api/distancematrix/json?origins=".$lat1.",".$long1."&destinations=".$lat2.",".$long2."&mode=driving&language=pl-PL";
    $ch = curl_init();
    curl_setopt($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);
    $dist = $response_a['rows'][0]['elements'][0]['distance']['text'];
    $time = $response_a['rows'][0]['elements'][0]['duration']['text'];
    return array('distance' => $dist, 'time' => $time);
}
while($row = $result->fetch_assoc()) {
//Start of  calculate distance and time
$lat1 = "-1.283180";
$long1 = "36.822462";
$lat2 = $row["lat"];
$long2 = $row["lng"];
$dist = GetDrivingDistance($lat1, $lat2, $long1, $long2);
$distance = $dist['distance'];
$time = $dist['time'];
//End of calculate distance and time
         echo "". $row["id"]. " ". $row["reg_number"]. " (" . $row["sacco"] . ") -$time\n";
     }
} else {
     echo "0 results";
}
$conn->close();