php - PHP:如何使用和维护 key ？

Question

我有以下数组(JSON格式化以便于查看):

{
  "23": {
    "price": "33.99"
  },
  "38": {
    "price": "30.86"
  },
  "51": {
    "price": "31.49"
  }
}

我想通过 price键对此进行排序，但是我希望结果还返回包含价格的元素的键，因此如下所示:

{
  "38": {
    "price": "30.86"
  },
  "51": {
    "price": "31.49"
  },
  "23": {
    "price": "33.99"
  }
}

我的 usort回调是这样的:

private function _price_sort($a, $b)
{
    if ($a['price'] == $b['price']) {
        return 0;
    }
    return ($a['price'] < $b['price']) ? -1 : 1;
}

...以正确的顺序返回数组，但没有元素容器:

[
  {
    "price": "30.86"
  },
  {
    "price": "31.49"
  },
  {
    "price": "33.99"
  }
]

我需要在回调函数或usort中做一些事情来保留键吗？

Answer 1

使用 uasort() 维护 key

This function sorts an array such that array indices maintain their correlation with the array elements they are associated with, using a user-defined comparison function.