如何在JavaScript中計算X天前

Question

在我的應用程序中，我正在訪問遠程URL並獲得如下所示的JSON響應。 JSON響應有一個名爲created_at的屬性。

在JavaScript中，我需要獲取當前日期減去（ - ）created_at日期並計算多少天前創建評論。

我該怎麼做？

{ 
    "id":12578834, 
    "title":"Joint R&D Has Its Ups and Downs", 
    "url":"http://semiengineering.com/joint-rd-has-its-ups-and-downs/", 
    "num_points":1, 
    "num_comments":0, 
    "author":"Lind5", 
    "created_at":"9/26/2016 2:28" 
} 

Answer 1

您可以創建幾天，然後通過減去today.getTime() - date.getTime()/NumOfMSecInDay來獲得差異。

此外，時間部分可能會導致一些問題，所以最好將其剝離。

var d = { 
 
    "id": 12578834, 
 
    "title": "Joint R&D Has Its Ups and Downs", 
 
    "url": "http://semiengineering.com/joint-rd-has-its-ups-and-downs/", 
 
    "num_points": 1, 
 
    "num_comments": 0, 
 
    "author": "Lind5", 
 
    "created_at": "9/26/2016 2:28" 
 
} 
 

 
var today = new Date(); 
 
var createdOn = new Date(d.created_at); 
 
var msInDay = 24 * 60 * 60 * 1000; 
 

 
createdOn.setHours(0,0,0,0); 
 
today.setHours(0,0,0,0) 
 

 
var diff = (+today - +createdOn)/msInDay 
 
console.log(diff)