json编码的php数组,在坐标变量输出周围加引号

我正在编写一个wordpress循环,它获取多个post并在基于php的数组中输出post自定义字段GeoJson coordinates数组。

$sFeatureCoordinates 变量。

  [
    [
      -0.7332730293273926,
      51.89886634382943
    ],
    [
      -0.7326534390449524,
      51.89770778622719
    ],
    [
      -0.7318434119224548,
      51.898079355455344
    ],
    [
      -0.7332730293273926,
      51.89886634382943
    ]
  ]

json_encode 格式化数组。

$arr = [
    'type' => 'FeatureCollection',
    'features' => []
];

// loop through each post
while($oQuery->have_posts()): $oQuery->the_post();

    // grab our type and coordinates
    $sFeatureType = get_field('geojson_feature_type');
    $sFeatureCoordinates = get_field('geojson_feature_coordinates');

    // add this to our features
    $arr['features'][] = [
        'type' => 'Feature',
        'properties' => [
            'id' => get_the_id(),
            'name' => get_the_title()
        ],
        'geometry' => [
            'type' => $sFeatureType,
            'coordinates' => [
                [ preg_replace('/\s+/', '', $sFeatureCoordinates) ]
            ]
        ]
    ];

endwhile;

$json = json_encode($arr);

下面是从上面的数组输出的json示例 http://myjson.com/pssis

我的问题是 coordinates 当它被编码的时候会被用引号括起来。

有什么办法能阻止我的行为吗 将内容用引号括起来 json\ U编码

非常感谢