JS-JSON:通过计算现在的时间差和JSON对象中的时间戳,在每个对象中添加一个密钥对。

const array = [{"id": 1,"timestamp": 1545311087282}, {"id": 2, "timestamp": 1545311148254}];
const now = new Date().getTime();

// New copy.
const newArray = array.map(o => ({...o, diff: now - o.timestamp}));

console.log(array);
console.log(newArray);

// Changes original. 
array.forEach(o => o.diff = now - o.timestamp);
console.log(array);

const array = [{"id": 1,"timestamp": 1545311087282}, {"id": 2, "timestamp": 1545311148254}];
const now = new Date().getTime();

// Difference in minutes.
const diff = time => new Date(now).getMinutes() - new Date(time).getMinutes();

// New copy.
const newArray = array.map(o => ({...o, minsDiff: diff(o.timestamp)}));

console.log(array);
console.log(newArray);

var arrofobj = [{"id": 1, "timestamp":1545311087282},{"id": 2, "timestamp":1545311148254}];
let now = new Date().getTime();
arrofobj.forEach(v => v.timestampdiff = now - v.timestamp);
console.log(arrofobj);