此问题在此处已有答案：

How do I loop through or enumerate a JavaScript object?（48个回答）
How to access the first property of a Javascript object?（23个回答）
三年前就关门了。
当我试图访问数据的第0个索引时，我得到了错误undefined，但当我试图打印出整个对象时，它工作正常。我无法访问任何元素或循环数据。data变量工作正常，但tSeries变量未定义。
这是一段代码：

var data;
var tSeries;


(async () => {
    const response = await fetch("https://www.alphavantage.co/query?function=TIME_SERIES_DAILY&symbol=IBM&apikey=" + key);
    apidata = await response.json();
    data = (apidata["Meta Data"]["2. Symbol"]);
    tSeries = (apidata["Time Series (Daily)"][0]);
    console.log(tSeries);
    
})();

字符串
下面是JSON响应代码：

{
    "Meta Data": {
        "1. Information": "Intraday (5min) open, high, low, close prices and volume",
        "2. Symbol": "IBM",
        "3. Last Refreshed": "2020-06-24 16:00:00",
        "4. Interval": "5min",
        "5. Output Size": "Compact",
        "6. Time Zone": "US/Eastern"
    },
    "Time Series (Daily)": {
        "2020-06-24 16:00:00": {
            "1. open": "116.4600",
            "2. high": "116.6700",
            "3. low": "116.3800",
            "4. close": "116.4900",
            "5. volume": "263785"
        },
        "2020-06-24 15:55:00": {
            "1. open": "116.8000",
            "2. high": "116.8600",
            "3. low": "116.3500",
            "4. close": "116.4700",
            "5. volume": "154646"
        },
        "2020-06-24 15:50:00": {
            "1. open": "117.0100",
            "2. high": "117.1400",
            "3. low": "116.8500",
            "4. close": "116.8500",
            "5. volume": "99465"
        },
        "2020-06-24 15:45:00": {
            "1. open": "116.6900",
            "2. high": "117.0400",
            "3. low": "116.6600",
            "4. close": "117.0100",
            "5. volume": "83736"
        }

型