Google表格：API返回的json标记未定义

Question

I've been trying to use an online API (albion-online-data.com) for a while in sheets, creating a little function to try to grab a specific identifier, sell_price_min, but the function keeps returning undefined.

I've been looking around for ages but haven't been able to find out what's wrong. Sorry, I'm new to APIs and google sheets in general. I used Logger.log, and it shows the correct contents after Json.parse, but when trying to use return w.sell_price_min; it always returns undefined.

Here's the code:

/**
 * Retrieve the current price for a given city.
 *
 */
function CURRENTPRICE(name, location, quality) {
    name = encodeURI(name);
    location = encodeURI(location);
    quality = encodeURI(quality);
    var response = UrlFetchApp.fetch("http://www.albion-online-data.com/api/v2/stats/Prices/" + name + "?locations=" + location + "&qualities=" + quality);
    var w = JSON.parse(response.getContentText());
    return w.sell_price_min;
}

and the API is: https://www.albion-online-data.com/api/v2/stats/prices/T4_BAG,T5_BAG?locations=Caerleon,Bridgewatch&qualities=2

which returns the following: (reformatted here with indentation and line breaks for readability)

[
  {
    "item_id": "T4_BAG",
    "city": "Bridgewatch",
    "quality": 2,
    "sell_price_min": 4000,
    "sell_price_min_date": "2019-09-02T22:20:00",
    "sell_price_max": 4444,
    "sell_price_max_date": "2019-09-02T22:20:00",
    "buy_price_min": 0,
    "buy_price_min_date": "0001-01-01T00:00:00",
    "buy_price_max": 0,
    "buy_price_max_date": "0001-01-01T00:00:00"
  },
  {
    "item_id": "T4_BAG",
    "city": "Caerleon",
    "quality": 2,
    "sell_price_min": 5571,
    "sell_price_min_date": "2019-09-03T11:05:00",
    "sell_price_max": 5571,
    "sell_price_max_date": "2019-09-03T11:05:00",
    "buy_price_min": 2375,
    "buy_price_min_date": "2019-09-03T08:41:00",
    "buy_price_max": 4020,
    "buy_price_max_date": "2019-09-03T08:41:00"
  },
  {
    "item_id": "T5_BAG",
    "city": "Bridgewatch",
    "quality": 0,
    "sell_price_min": 20000,
    "sell_price_min_date": "2019-09-01T14:00:00",
    "sell_price_max": 22100,
    "sell_price_max_date": "2019-09-01T14:00:00",
    "buy_price_min": 0,
    "buy_price_min_date": "0001-01-01T00:00:00",
    "buy_price_max": 0,
    "buy_price_max_date": "0001-01-01T00:00:00"
  },
  {
    "item_id": "T5_BAG",
    "city": "Caerleon",
    "quality": 2,
    "sell_price_min": 23897,
    "sell_price_min_date": "2019-09-03T11:03:00",
    "sell_price_max": 26376,
    "sell_price_max_date": "2019-09-03T11:03:00",
    "buy_price_min": 15000,
    "buy_price_min_date": "2019-09-02T22:21:00",
    "buy_price_max": 22550,
    "buy_price_max_date": "2019-09-02T22:21:00"
  }
]

and the results should be: 4000?

Sorry for any hassle... I've been stumped for literally hours .-.

Answer 1

You are accessing a JSON array. So it should be

for(var i = 0; i < w.length; i++) {
    var obj = w[i];

    console.log(obj.sell_price_min);
} 

If you want to get the first value of the array put

return w[0].sell_price_min