Flutter: Remove leading zeros from time format

Question

I am receiving a string in this format 'HH:mm:ss' and I need to get rid of the leading zeros OR convert it to minutes/hours. Is there a RegExp to achieve this?

Examples with no leading zeros:

00:03:15 => 3:15
10:10:10 => 10:10:10
00:00:00 => 0:00
04:00:00 => 4:00:00
00:42:32 => 42:32
00:00:18 => 0:18
00:00:08 => 0:08

Examples of time converted to minutes/hours

00:07:00 => 7 min
00:10:30 => 10:30 min
01:40:00 => 1h 40 min

Solution 1

Try the following

Add intl package to your pubspec.yaml file.

import 'package:intl/intl.dart';

DateFormat dateFormat = DateFormat("HH:mm");

Converting DateTime object to String

DateTime yourDate = DateTime.now());
String string = dateFormat.format(yourDate);

Can also try this

DateTime yourDate = DateTime.now();
String string =  new DateFormat.Hm().format(yourDate);    // force 24 hour time

Update

To Parse a String to a Date you can use this

DateFormat df = DateFormat('HH:mm:ss');
DateTime dt = df.parse('00:07:00');
String string = DateFormat.Hm().format(dt);

References

• DateFormat Class

Solution 2

Looks like at this point just using a single char (eg, M instead of MM) in the format string handles the trim of leading zeroes:

BEFORE:

// Output: 01/01/2021, 02:41 PM
static final dateFormatLeadingZeros = new DateFormat('MM/dd/yyyy, hh:mm a');

AFTER:

// Output: 1/1/2021, 2:41 PM
static final dateFormatTrimmed = new DateFormat('M/d/yyyy, h:mm a');