PHP JSON将输出数字编码为字符串

Question

我正在尝试使用PHP和MySQL输出一个JSON字符串，但是纬度和经度输出为一个值括有引号的字符串。当我尝试将标记添加到google地图时，这会导致一个问题。

下面是我的代码：

$sql = mysql_query('SELECT * FROM markers WHERE address !=""');
$results = array();
while($row = mysql_fetch_array($sql))
{
   $results[] = array(
      'latitude' =>$row['lat'],
      'longitude' => $row['lng'],
      'address' => $row['address'],
      'project_ID' => $row['project_ID'],
      'marker_id' => $row['marker_id']
   );
}
$json = json_encode($results);

echo "{\"markers\":";
echo $json;
echo "}";

以下是预期的输出：

{"markers":[{"latitude":0.000000,"longitude":0.000000,"address":"2234 2nd Ave, Seattle, WA","project_ID":"7","marker_id":"21"}]}

下面是我得到的输出：

{"markers":[{"latitude":"0.000000","longitude":"0.000000","address":"2234 2nd Ave, Seattle, WA","project_ID":"7","marker_id":"21"}]}

请注意纬度和经度值两边的引号。

Answer 1

您也可以尝试

echo json_encode( $results, JSON_NUMERIC_CHECK );

一些参考：

PHP JSON constants

Answer 2

$results[] = array(
  'latitude' => (float)$row['lat'],
  'longitude' => (float)$row['lng'],
  'address' => $row['address'],
  'project_ID' => $row['project_ID'],
  'marker_id' => $row['marker_id']
);

纬度和经度应该是一个浮点数，但您可以尝试这样做

Answer 3

您可能不知道:在PHP语言中从MySQL中检索数据时，无论实际值是什么，您都将always get字符串返回。然而，对float进行简单的类型转换应该可以解决这个问题：

$sql = mysql_query('SELECT * FROM markers WHERE address !=""');
$results = array();
while($row = mysql_fetch_array($sql))
{
   $results[] = array(
      'latitude' => (float) $row['lat'],
      'longitude' => (float) $row['lng'],
      'address' => $row['address'],
      'project_ID' => $row['project_ID'],
      'marker_id' => $row['marker_id']
   );
}
$json = json_encode($results);

echo "{\"markers\":";
echo $json;
echo "}";

或者，由于浮点数可能不足以存储经纬度坐标，请将它们存储为字符串，并使用字符串操作函数(如str_replace )动态删除引号。