How do you format "2018-09-21 16:00:00 -0500" in google apps script?

Question

I have a date in the format "yyyy-mm-dd hh:MM:ss timezone" (i.e."2018-09-21 16:00:00 -0500") When use code:

var d = new Date("2018-09-21 16:00:00 -0500")

The debug shows me

d = Invalid Date

I am trying to reformat the date as below,

var days = ["SUN", "MON", "TUE", "WED", "THU", "FRI", "SAT"];


var day = days[d.getDay()];
var hh = d.getHours();
var mm = d.getMinutes()

if(hh < 10) {hh = "0"+hh}
if(mm < 10) {mm = "0"+mm}

return day+" "+hh+mm

What is the best way to format this date?

Answer 1

• You want to parse the string value of yyyy-mm-dd hh:MM:ss timezone as a date object.

If my understanding is correct, how about this answer? I think that there are several answers for your situation. So please think of this as one of them.

When I saw the format, I thought that RFC3339 is close to the format. So how about the following flow?

1. Split the value by which is a space.
2. Join 1st and 2nd element of the splited value by "T".
3. Add last element to the joined value.

When 2018-09-21 16:00:00 -0500 is used for this flow, the value is converted to 2018-09-21T16:00:00-0500. This can be used as the RFC3339 type. By this flow, yyyy-mm-dd hh:MM:ss timezone can be parsed as the date object.

Sample script:

Pattern 1:

The sample script which reflected above flow is as follows.

var str = "2018-09-21 16:00:00 -0500"; // yyyy-mm-dd hh:MM:ss timezone

var ar = str.split(" "); // Added
var str = ar.slice(0, 2).join("T") + ar[2]; // Added: Here str is "2018-09-21T16:00:00-0500".
var d = new Date(str);

var days = ["SUN", "MON", "TUE", "WED", "THU", "FRI", "SAT"];
var day = days[d.getDay()];
var hh = d.getHours();
var mm = d.getMinutes()
if(hh < 10) {hh = "0"+hh}
if(mm < 10) {mm = "0"+mm}

Logger.log(day+" "+hh+mm) // Added

return day+" "+hh+mm

Pattern 2:

As an another pattern, how about this script? In Google Apps Script, you can also use Utilities.formatDate().

var str = "2018-09-21 16:00:00 -0500";
var ar = str.split(" ");
var r = ar.slice(0, 2).join("T") + ar[2];
var d = new Date(r);
var res = Utilities.formatDate(d, Session.getScriptTimeZone(), "E hhmm").toUpperCase();
Logger.log(res)

Note:

• If the format is different from yyyy-mm-dd hh:MM:ss timezone, this script might not be able to be used. Please be careful about this.

Reference:

• RFC3339
• formatDate(date, timeZone, format)

If I misunderstand your question, I'm sorry.

Answer 2

Your date is very close to ISO ! I would start by converting to ISO. For what you want, you don't need the timezone, so life will be simpler if we forget it...

var parts = '2018-09-21 16:00:00 -0500'.split(' ');
var myDate = new Date(parts[0] + 'T' +  parts[1] + 'Z');
console.log(myDate)

// Now serialize...

var nearlyThere = myDate.toLocaleDateString(
    'en-EN',
    {timeZone:'UTC', weekday:'short',hour:'2-digit',minute:'2-digit',hour12:false }
)
console.log(nearlyThere.replace(' ','').replace(':',' ').toUpperCase())