将键推入数组= key = value

Question

我有一个带有乘用户的数据库，并且位置数据。我把它们放在像下面的数组中

id--username--lat-----lng
1 | user1  |  56.86 | 7.85
2 | user2  |  48.3  | 9.323
3 | user3  |  83.22 | 84.2
etc...

数组$用户看起来像：

$users = Array( [0] => ( [id] => 1[0] => 1[username] => user1[1] => user1[lat] => 56.86[2] => 56.86[lng] => 7.85[3] => 7.85)
[1] => ( [id] => 2[0] => 2[username] => user2[1] => user2[lat] => 48.3[2] => 48.3[lng] => 9.323[3] => 9.323)
[2] => ( [id] => 3[0] => 3[username] => user3[1] => user3[lat] => 83.22[2] => 83.22[lng] => 84.2[3] => 84.2))

我用mylat和mylng从每个用户那里计算出LAT和LNG的距离。然后，我想将$ $ distn推到带有用户ID值的位置/密钥ID的数组$ uders中，但我不知道如何：

    foreach ($users as $row) { //for each user in database calculate the distance and set it to the variable $distn
    $dist = 0.0;
        $x1 = $mylng;
        $x2 = $row['lng'];
        $y1 = $mylat;
        $y2 = $row['lat'];
        $dist = acos(sin($x1=deg2rad($x1))*sin($x2=deg2rad($x2))+cos($x1)*cos($x2)*cos(deg2rad($y2) - deg2rad($y1)))*(6378.137);
        $distn = FLOOR ( ROUND($dist,1) * 2 ) / 2 ;
      push $distn into $users where id=row['id'] // this is just a sample not real code
    }

以使数组现在看起来应该像这样：

$users = Array( [0] => ( [id] => 1[0] => 1[dist] => 3.0[1] => 3.0[username] => user1[2] => user1[lat] => 56.86[3] => 56.86[lng] => 7.85[4] => 7.85)
[1] => ( [id] => 2[0] => 2[dist] => 1.5[1] => 1.5[username] => user2[2] => user2[lat] => 48.3[3] => 48.3[lng] => 9.323[4] => 9.323)
[2] => ( [id] => 3[0] => => 3[dist] => 1.0[1] 1.0[username] => user3[2] => user3[lat] => 83.22[3] => 83.22[lng] => 84.2[4] => 84.2))

$ $ distn与键" dist"添加了键" id"之后，每个用户的值。如果有效，我想对数组进行排序，以便首先显示具有最低" DIST"的用户：

user3 1km distance
user2 1.5km distance
user1 3km distance

我该怎么做？感谢您的帮助：）

Answer 1

在第一部分中，使用 $key => $value语法用于 foreach()：

foreach ($users as $key => $row) {
    // code
    $users[$key]['dist'] = $distn;
}

对于排序，我将提取列并按原始分类：

array_multisort(array_column($users, 'dist'), SORT_ASC, $users);

另外，由于您使用的是一个关联数组，请考虑：

$users = $statement->fetchAll(PDO::FETCH_ASSOC);