Question

我尝试使用PHP curl连接Coinmarketcap的API，以从中获取实时比特币价格。关键是它提供的输出太混乱了，以至于我不知道如何从中取出“价格”。周围也有类似的问题，但不幸的是，这些答复对我没有帮助。所以我想知道如何从API给出的回报中去除比特币的价格？由于我仍然是新手，因此似乎在误解数组和对象。这是“ die and dump”返回的内容：

  #data: array:1 [▼
    "response" => """
      {
          "status": {
              "timestamp": "2019-04-15T14:03:35.573Z",
              "error_code": 0,
              "error_message": null,
              "elapsed": 5,
              "credit_count": 1
          },
          "data": [
              {
                  "id": 1,
                  "name": "Bitcoin",
                  "symbol": "BTC",
                  "slug": "bitcoin",
                  "circulating_supply": 17646787,
                  "total_supply": 17646787,
                  "max_supply": 21000000,
                  "date_added": "2013-04-28T00:00:00.000Z",
                  "num_market_pairs": 7253,
                  "tags": [
                      "mineable"
                  ],
                  "platform": null,
                  "cmc_rank": 1,
                  "last_updated": "2019-04-15T14:02:29.000Z",
                  "quote": {
                      "USD": {
                          "price": 5166.87433557,
                          "volume_24h": 11238888046.6075,
                          "percent_change_1h": 0.0140845,
                          "percent_change_24h": 1.39641,
                          "percent_change_7d": -0.981349,
                          "market_cap": 91178730855.57031,
                          "last_updated": "2019-04-15T14:02:29.000Z"
                      }
                  }
              }
          ]
      }
      """
  ]

以下是从API请求的代码：

   function apiGet($url)
    {
        $parameters = [
            'start' => '1',
            'limit' => '3',
        ];
        $query = http_build_query($parameters);

        $curl = curl_init();

        curl_setopt_array($curl, array(
            CURLOPT_URL => "$url",
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_ENCODING => "",
            CURLOPT_TIMEOUT => 30000,
            CURLOPT_POST => true,
            CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
            CURLOPT_CUSTOMREQUEST => "GET",
            CURLOPT_HTTPHEADER => array(
                'Content-Type: application/json',
                'Accept-Encoding: deflate, gzip',
                'X-CMC_PRO_API_KEY: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx',


            ),
        )
        );

        $response = curl_exec($curl);
        $err = curl_error($curl);
        curl_close($curl);

        if ($err) {
            echo "cURL Error #:" . $err;
        } else {
            print_r(json_decode($response));
        }
        return view('price', compact('response'));
    }

        $parameters = [
             'start' => '1',
             'limit' => '1',
         ];
         $query = http_build_query($parameters);
         $btc = new \App\Http\Controllers\CoinsController();
         $result = $btc->apiGet('https://pro-api.coinmarketcap.com/v1/cryptocurrency/listings/latest'."?".$query);

         dd($result);

Answer 1

那是一个嵌套的键值数组，其中包含一个json字符串。您可以这样获得价格：

$price = json_decode($result['response'])->data[0]->quote->USD->price;

Answer 2

据您所知。您可以使用Laravel提供的Arr::get()帮助程序。参见docs：

use \Illuminate\Support\Arr;

...

$data = json_decode($result['response'], true);

$price = Arr::get($data, 'data.0.quote.USD.price');

试图从这个令人困惑的StdClass中取出数据

2 个答案: