Check if date is a valid one

Question

Following is the scenario:

I have a String date and a date format which is different. Ex.:
date: 2016-10-19
dateFormat: \"DD-MM-YYYY\".

Answer 1

I use moment along with new Date to handle cases of undefined data values:

const date = moment(new Date("2016-10-19"));

because of: moment(undefined).isValid() == true

where as the better way: moment(new Date(undefined)).isValid() == false