JavaScript:从键值数组中提取特定键的值，并将其存储在新数组中

Question

我有一个'多维键值数组，如下所示：

'[[
{"_time":"2022-01-03T00:00:00Z","_value":10.70140000000014,"ts":1641168000000},
{"_time":"2022-01-04T00:00:00Z","_value":13.002499999999767,"ts":1641254400000},
{"_time":"2022-01-05T00:00:00Z","_value":16.171700000000182,"ts":1641340800000},
{"_time":"2022-01-06T00:00:00Z","_value":17.48929999999981,"ts":1641427200000},
]]'

我需要用这种方式在一个新的变量中获得每个值：

[10.70140000000014,13.002499999999767,16.171700000000182,17.48929999999981]

我尝试了地图，但这与我的需求不匹配：

function getPreparedData(data) {
if (data) {
return data[0].map(elm => ({
a: elm._value
}));
}
return [];
};

我该如何解决这个问题？

感谢

Frank

Answer 1

在您的示例中，函数getPreparedData返回对象数组。您实际上想要返回一个值数组(其中值只是_value属性的值(

const data = [[
{"_time":"2022-01-03T00:00:00Z","_value":10.70140000000014,"ts":1641168000000},
{"_time":"2022-01-04T00:00:00Z","_value":13.002499999999767,"ts":1641254400000},
{"_time":"2022-01-05T00:00:00Z","_value":16.171700000000182,"ts":1641340800000},
{"_time":"2022-01-06T00:00:00Z","_value":17.48929999999981,"ts":1641427200000},
]];
function getPreparedData(data) {
return data[0].map(elm => elm._value)
};
const res = getPreparedData(data);
console.log(res);