获取两个日期之间的日期时间差异

Question

Refferred Date difference in hours - Angular 2，这不是返回

let creationDate =params.data.createdTime;
let incidentDate= params.data.incidentTime;
let diffInMs = Date.parse(creationDate) - Date.parse(incidentDate);
let diffInHours = diffInMs / 1000 / 60 / 60;

返回错误的答案或大多数情况下NaN，

Date is in this format - `08/03/2017 10:52:58 AM - 06/03/2017 10:48:15 PM`

DATEFORMAT：dd / MM / yyyy hh：mm：ss a