Moment.js加上天数，就会得到以毫秒为单位的差值

Question

我有以下代码，其中我从api接收时间戳，然后添加x天数，然后以毫秒为单位获得差异：-

const dateFromApi = "2020-08-28 16:36:58";
const durationInDay = 1;
var createdAt = moment.tz(dateFromApi, "Asia/Kuwait");
const added = createdAt.add(durationInDay, "days");
var diffInMilliseconds = added.diff(createdAt);
console.log(diffInMilliseconds);

CodeSandBox

差别总是给0。

如何使上面的代码以毫秒为单位返回差异？

Answer 1

.add文档中的As

通过添加时间来更改原始时刻。

所以当你做这个

const added = createdAt.add(durationInDay, "days");
var diffInMilliseconds = added.diff(createdAt);

它还添加到createdAt本身，因此毫无疑问比较返回0

在这种情况下，一个简单的修复方法是将createdAt克隆到不同的对象中，只需使用.clone((

const added = createdAt.clone().add(durationInDay, "days");
var diffInMilliseconds = added.diff(createdAt);

const dateFromApi = "2020-08-28 16:36:58";
const durationInDay = 1;
var createdAt = moment.tz(dateFromApi, "Asia/Kuwait");
const added = createdAt.clone().add(durationInDay, "days");
var diffInMilliseconds = added.diff(createdAt);
console.log(diffInMilliseconds);

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