I have a JSON response ing with the object of '20180715' and I need to convert that string to date, for example:

let dateString = '20180715';

I tried Date testdate = new Date (dateString); //fails.

How can I convert it to a date object in TypeScript?

Thanks in advance!

I have a JSON response ing with the object of '20180715' and I need to convert that string to date, for example:

let dateString = '20180715';

I tried Date testdate = new Date (dateString); //fails.

How can I convert it to a date object in TypeScript?

Thanks in advance!

• javascript
• string
• typescript
• date

2 Answers 2

If the actual structure of the date in the string doesn't change, you can just simply get the parts of the string using the .substr function.

Keep in mind, that the month is 0-based, hence the month have to be decreased by 1.

const dateString = '20180715';
const year = dateString.substr(0, 4);
const month = dateString.substr(4, 2) - 1;
const day = dateString.substr(6, 2);
const date = new Date(year, month, day);

console.log(date.toString());

You can also use RegEx to parse. Notice the decremental operator (--) for the month, since Date indexes the month at 0. For anything more advanced, please refer to moment.js, which includes many formatting templates.

const re  = /(\d{4})(\d{2})(\d{2})/;
const str = '20180715';
if (re.test(str)) {
  const dt = new Date(RegExp.$1, --RegExp.$2, RegExp.$3);
  console.log(dt);
}