拆分并解析字符串以创建关联数组的数组

Question

如何将下面的字符串转换成二维数组？

$coordinates = "9.499819 123.920318,9.490845 123.916563,9.484644 123.922292,9.49148 123.931519,9.499755 123.925683,9.499819 123.920318";

我想用逗号分隔值对，然后用分隔符分隔每对值 space 以形成包含浮点型值的关联行。

期望的输出：

$polygon = array(
    array('lat' => 9.499819, 'lng' => 123.920318),
    array('lat' => 9.490845, 'lng' => 123.916563),
    array('lat' => 9.484644, 'lng' => 123.922292),
    array('lat' => 9.49148, 'lng' => 123.931519),
    array('lat' => 9.499755, 'lng' => 123.925683),
    array('lat' => 9.499819, 'lng' => 123.920318)
);

Answer 1

对于新贡献者，我认为使用 foreach 的解决方案更容易理解。这些步骤在代码中有注释。

$coordinates = "9.499819 123.920318,9.490845 123.916563,9.484644 123.922292,9.49148 123.931519,9.499755 123.925683,9.499819 123.920318";

$polygon = explode(',',$coordinates);
/*
array (
  0 => "9.499819 123.920318",
  1 => "9.490845 123.916563",
*/

foreach($polygon as $index => $latLng){
  //The element $latLng is split into two variables with list and explode.
  list($lat,$lng) = explode(' ',$latLng);

  //The elements are replaced by a new array with the variables $lat and $lng as float
  $polygon[$index] = ['lat' => (float)$lat, 'lng' => (float)$lng];
}

//test output
echo '<pre>';
var_export($polygon);

输出：

array (
  0 => 
  array (
    'lat' => 9.499819,
    'lng' => 123.920318,
  ),
  1 => 
  array (
    'lat' => 9.490845,
    'lng' => 123.916563,
  ),
  2 => 
  array (
    'lat' => 9.484644,
    'lng' => 123.922292,
  ),
  3 => 
  array (
    'lat' => 9.49148,
    'lng' => 123.931519,
  ),
  4 => 
  array (
    'lat' => 9.499755,
    'lng' => 123.925683,
  ),
  5 => 
  array (
    'lat' => 9.499819,
    'lng' => 123.920318,
  ),
)

添加 2022-03-04：

这个 one-liner 和 preg_match_all 已经 returns 完整的结果，但有额外的数字键。

preg_match_all('~(?<lat>[0-9.]+) (?<lng>[0-9.]+),?~', $coordinates, $match,PREG_SET_ORDER);

array_map可用于去除多余的值。

$polygon = array_map(
  function($row){return ['lat' => $row['lat'],'lng' => $row['lng']];},
  $match
);

Answer 2

通过迭代调用 sscanf()，您可以指定解析值的数据类型并将这些值推送到结果数组中。

代码：(Demo)

$coordinates = "9.499819 123.920318,9.490845 123.916563,9.484644 123.922292,9.49148 123.931519,9.499755 123.925683,9.499819 123.920318";

foreach (explode(',', $coordinates) as $i => $latLng) {
    sscanf($latLng, '%f %f', $result[$i]['lat'], $result[$i]['lng']);
};
var_export($result);

输出：

array (
  0 => 
  array (
    'lat' => 9.499819,
    'lng' => 123.920318,
  ),
  1 => 
  array (
    'lat' => 9.490845,
    'lng' => 123.916563,
  ),
  2 => 
  array (
    'lat' => 9.484644,
    'lng' => 123.922292,
  ),
  3 => 
  array (
    'lat' => 9.49148,
    'lng' => 123.931519,
  ),
  4 => 
  array (
    'lat' => 9.499755,
    'lng' => 123.925683,
  ),
  5 => 
  array (
    'lat' => 9.499819,
    'lng' => 123.920318,
  ),
)

拆分并解析字符串以创建关联数组的数组

Split and parse a string to create an array of associative arrays

php

types

split

text-parsing

multidimensional-array