如何檢查數組中是否存在特定的Object元素（不是屬性）？

Question

我嘗試使用.includes（）方法，但無法正常工作。

data = [{
    "Global Quote": {
        "01. symbol": "TSLA",
        "02. open": "256.7100",
        "03. high": "260.4800",
        "04. low": "254.5100",
        "05. price": "260.1700",
        "06. volume": "4967930",
        "07. latest trading day": "2019-07-23",
        "08. previous close": "255.6800",
        "09. change": "4.4900",
        "10. change percent": "1.7561%"
    }
}]

data.includes("Global Quote") ? console.log("found") : console.log("not 
found");

每次控制台日志“未找到” ...

Answer 1

如果要檢查數組是否包含至少一個具有特定屬性的對象，則可以使用some

找到屬性的示例：

 var data = [{ "Global Quote": {} }] data.some(o => "Global Quote" in o) ? console.log("found") : console.log("not found "); 

找不到屬性的示例：

 var data = [{ "Not Global Quote": {}, }, { "Not Global Quote Also": {}, } ] data.some(o => "Global Quote" in o) ? console.log("found") : console.log("not found "); 

Answer 2

使用data.includes(...)檢查屬性時，您在對象中的位置不正確。

您必須更深入一層，並使用hasOwnProperty方法檢查該屬性。

您的代碼將如下所示：

const data = [{
    "Global Quote": {
        "01. symbol": "TSLA",
        "02. open": "256.7100",
        "03. high": "260.4800",
        "04. low": "254.5100",
        "05. price": "260.1700",
        "06. volume": "4967930",
        "07. latest trading day": "2019-07-23",
        "08. previous close": "255.6800",
        "09. change": "4.4900",
        "10. change percent": "1.7561%"
    }
}]


data[0].hasOwnProperty('Global Quote') ? console.log('found') : console.log('not found);

Answer 3

假設在該數組中將有多個對象，則可以使用some 。

 const data = [{ "Global Quote": { "01. symbol": "TSLA", "02. open": "256.7100", "03. high": "260.4800", "04. low": "254.5100", "05. price": "260.1700", "06. volume": "4967930", "07. latest trading day": "2019-07-23", "08. previous close": "255.6800", "09. change": "4.4900", "10. change percent": "1.7561%" } }]; function findKey(arr, key) { return arr.some(obj => Object.keys(obj)[0] === key); } console.log(findKey(data, 'Global Test')); console.log(findKey(data, 'Global Quote'));