Converting timestamp - dart

Question

I couldn't find a solution to this, I'm grabbing data from firebase and one of the fields is a timestamp which looks like this -> 1522129071. How to convert it to a date?
Swift example (works) :
func readTimestamp(timestamp: Int) {
let now = Date()
let dateFormatter = DateFormatter()
let date = Date(timeIntervalSince1970: Double(timestamp))
let components = Set<Calendar.Component>([.second, .minute, .hour, .day, .weekOfMonth])
let diff = Calendar.current.dateComponents(components, from: date, to: now)
var timeText = ""
dateFormatter.locale = .current
dateFormatter.dateFormat = "HH:mm a"
if diff.second! <= 0 || diff.second! > 0 && diff.minute! == 0 || diff.minute! > 0 && diff.hour! == 0 || diff.hour! > 0 && diff.day! == 0 {
timeText = dateFormatter.string(from: date)
}
if diff.day! > 0 && diff.weekOfMonth! == 0 {
timeText = (diff.day == 1) ? "\(diff.day!) DAY AGO" : "\(diff.day!) DAYS AGO"
}
if diff.weekOfMonth! > 0 {
timeText = (diff.weekOfMonth == 1) ? "\(diff.weekOfMonth!) WEEK AGO" : "\(diff.weekOfMonth!) WEEKS AGO"
}
return timeText
}
My attempt at Dart:
String readTimestamp(int timestamp) {
var now = new DateTime.now();
var format = new DateFormat('HH:mm a');
var date = new DateTime.fromMicrosecondsSinceEpoch(timestamp);
var diff = date.difference(now);
var time = '';
if (diff.inSeconds <= 0 || diff.inSeconds > 0 && diff.inMinutes == 0 || diff.inMinutes > 0 && diff.inHours == 0 || diff.inHours > 0 && diff.inDays == 0) {
time = format.format(date); // Doesn't get called when it should be
} else {
time = diff.inDays.toString() + 'DAYS AGO'; // Gets call and it's wrong date
}
return time;
}
And it returns dates/times that are waaaaaaay off.
UPDATE:
String readTimestamp(int timestamp) {
var now = new DateTime.now();
var format = new DateFormat('HH:mm a');
var date = new DateTime.fromMicrosecondsSinceEpoch(timestamp * 1000);
var diff = date.difference(now);
var time = '';
if (diff.inSeconds <= 0 || diff.inSeconds > 0 && diff.inMinutes == 0 || diff.inMinutes > 0 && diff.inHours == 0 || diff.inHours > 0 && diff.inDays == 0) {
time = format.format(date);
} else {
if (diff.inDays == 1) {
time = diff.inDays.toString() + 'DAY AGO';
} else {
time = diff.inDays.toString() + 'DAYS AGO';
}
}
return time;
}

Answer 1

Your timestamp format is in fact in Seconds (Unix timestamp) as opposed to microseconds. If so the answer is as follows:
Change:
var date = new DateTime.fromMicrosecondsSinceEpoch(timestamp);
to
var date = DateTime.fromMillisecondsSinceEpoch(timestamp * 1000);

Answer 2

From milliseconds:
var millis = 978296400000;
var dt = DateTime.fromMillisecondsSinceEpoch(millis);
// 12 Hour format:
var d12 = DateFormat('MM/dd/yyyy, hh:mm a').format(dt); // 12/31/2000, 10:00 PM
// 24 Hour format:
var d24 = DateFormat('dd/MM/yyyy, HH:mm').format(dt); // 31/12/2000, 22:00
From Firestore:
Map<String, dynamic> map = docSnapshot.data()!;
DateTime dt = (map['timestamp'] as Timestamp).toDate();
Converting one format to other:
12 Hour to 24 Hour:
var input = DateFormat('MM/dd/yyyy, hh:mm a').parse('12/31/2000, 10:00 PM');
var output = DateFormat('dd/MM/yyyy, HH:mm').format(input); // 31/12/2000, 22:00
24 Hour to 12 Hour:
var input = DateFormat('dd/MM/yyyy, HH:mm').parse('31/12/2000, 22:00');
var output = DateFormat('MM/dd/yyyy, hh:mm a').format(input); // 12/31/2000, 10:00 PM
Use intl package (for formatting)

Answer 3

Full code for anyone who needs it:
String readTimestamp(int timestamp) {
var now = DateTime.now();
var format = DateFormat('HH:mm a');
var date = DateTime.fromMillisecondsSinceEpoch(timestamp * 1000);
var diff = now.difference(date);
var time = '';
if (diff.inSeconds <= 0 || diff.inSeconds > 0 && diff.inMinutes == 0 || diff.inMinutes > 0 && diff.inHours == 0 || diff.inHours > 0 && diff.inDays == 0) {
time = format.format(date);
} else if (diff.inDays > 0 && diff.inDays < 7) {
if (diff.inDays == 1) {
time = diff.inDays.toString() + ' DAY AGO';
} else {
time = diff.inDays.toString() + ' DAYS AGO';
}
} else {
if (diff.inDays == 7) {
time = (diff.inDays / 7).floor().toString() + ' WEEK AGO';
} else {
time = (diff.inDays / 7).floor().toString() + ' WEEKS AGO';
}
}
return time;
}
Thank you Alex Haslam for the help!

Answer 4

if anyone come here to convert firebase Timestamp here this will help
Timestamp time;
DateTime.fromMicrosecondsSinceEpoch(time.microsecondsSinceEpoch)

Answer 5

If you are using firestore (and not just storing the timestamp as a string) a date field in a document will return a Timestamp. The Timestamp object contains a toDate() method.
Using timeago you can create a relative time quite simply:
_ago(Timestamp t) {
return timeago.format(t.toDate(), 'en_short');
}
build() {
return Text(_ago(document['mytimestamp'])));
}
Make sure to set _firestore.settings(timestampsInSnapshotsEnabled: true); to return a Timestamp instead of a Date object.

Answer 6

To convert Firestore Timestamp to DateTime object just use .toDate() method.
Example:
Timestamp now = Timestamp.now();
DateTime dateNow = now.toDate();
As you can see in docs

Answer 7

Just make sure to multiply by the right factor:
Micro: multiply by 1000000 (which is 10 power 6)
Milli: multiply by 1000 (which is 10 power 3)
This is what it should look like in Dart:
var date = new DateTime.fromMicrosecondsSinceEpoch(timestamp * 1000000);
Or
var date = new DateTime.fromMillisecondsSinceEpoch(timestamp * 1000);

Answer 8

meh, just use https://github.com/andresaraujo/timeago.dart library; it does all the heavy-lifting for you.
EDIT:
From your question, it seems you wanted relative time conversions, and the timeago library enables you to do this in 1 line of code. Converting Dates isn't something I'd choose to implement myself, as there are a lot of edge cases & it gets fugly quickly, especially if you need to support different locales in the future. More code you write = more you have to test.
import 'package:timeago/timeago.dart' as timeago;
final fifteenAgo = DateTime.now().subtract(new Duration(minutes: 15));
print(timeago.format(fifteenAgo)); // 15 minutes ago
print(timeago.format(fifteenAgo, locale: 'en_short')); // 15m
print(timeago.format(fifteenAgo, locale: 'es'));
// Add a new locale messages
timeago.setLocaleMessages('fr', timeago.FrMessages());
// Override a locale message
timeago.setLocaleMessages('en', CustomMessages());
print(timeago.format(fifteenAgo)); // 15 min ago
print(timeago.format(fifteenAgo, locale: 'fr')); // environ 15 minutes
to convert epochMS to DateTime, just use...
final DateTime timeStamp = DateTime.fromMillisecondsSinceEpoch(1546553448639);

Answer 9

How to implement:
import 'package:intl/intl.dart';
getCustomFormattedDateTime(String givenDateTime, String dateFormat) {
// dateFormat = 'MM/dd/yy';
final DateTime docDateTime = DateTime.parse(givenDateTime);
return DateFormat(dateFormat).format(docDateTime);
}
How to call:
getCustomFormattedDateTime('2021-02-15T18:42:49.608466Z', 'MM/dd/yy');
Result:
02/15/21
Above code solved my problem. I hope, this will also help you. Thanks for asking this question.

Answer 10

I don't know if this will help anyone. The previous messages have helped me so I'm here to suggest a few things:
import 'package:intl/intl.dart';
DateTime convertTimeStampToDateTime(int timeStamp) {
var dateToTimeStamp = DateTime.fromMillisecondsSinceEpoch(timeStamp * 1000);
return dateToTimeStamp;
}
String convertTimeStampToHumanDate(int timeStamp) {
var dateToTimeStamp = DateTime.fromMillisecondsSinceEpoch(timeStamp * 1000);
return DateFormat('dd/MM/yyyy').format(dateToTimeStamp);
}
String convertTimeStampToHumanHour(int timeStamp) {
var dateToTimeStamp = DateTime.fromMillisecondsSinceEpoch(timeStamp * 1000);
return DateFormat('HH:mm').format(dateToTimeStamp);
}
int constructDateAndHourRdvToTimeStamp(DateTime dateTime, TimeOfDay time ) {
final constructDateTimeRdv = dateTimeToTimeStamp(DateTime(dateTime.year, dateTime.month, dateTime.day, time.hour, time.minute)) ;
return constructDateTimeRdv;
}

Answer 11

Assuming the field in timestamp firestore is called timestamp, in dart you could call the toDate() method on the returned map.
// Map from firestore
// Using flutterfire package hence the returned data()
Map<String, dynamic> data = documentSnapshot.data();
DateTime _timestamp = data['timestamp'].toDate();

Answer 12

Simply call this method to return your desired DateTime value in String.
String parseTimeStamp(int value) {
var date = DateTime.fromMillisecondsSinceEpoch(value * 1000);
var d12 = DateFormat('MM-dd-yyyy, hh:mm a').format(date);
return d12;
}
Example: if you pass the TimeStamp value 1636786003, you will get the result as
11-12-2021, 10:46PM

Answer 13

If you are here to just convert Timestamp into DateTime,
Timestamp timestamp = widget.firebaseDocument[timeStampfield];
DateTime date = Timestamp.fromMillisecondsSinceEpoch(
timestamp.millisecondsSinceEpoch).toDate();

Answer 14

I tested this one and it works
// Map from firestore
// Using flutterfire package hence the returned data()
Map<String, dynamic> data = documentSnapshot.data();
DateTime _timestamp = data['timestamp'].toDate();
Test details can be found here: https://www.youtube.com/watch?v=W_X8J7uBPNw&feature=youtu.be

Answer 15

Print DateTime, TimeStamp as string from Firebase Firestore:
Timestamp t;
String s;
DateTime d;
//Declaring Variables
snapshots.data.docs[index]['createdAt'] is Timestamp
? t = snapshots.data.docs[index]['createdAt']
: s =
snapshots.data.docs[index]['createdAt'].toString();
//check createdAt field Timestamp or DateTime
snapshots.data.docs[index]['createdAt'] is Timestamp
? d = t.toDate()
: s =
snapshots.data.docs[index]['createdAt'].toString();
print(s.toString()); //Print Date and Time if DateTime
print(d.toString()); //Print Date and Time if TimeStamp

Answer 16

Recently I've faced the same issue. so I'm using simple logic.
Very simple to Convert TimeStamp to DateTime. We can use this get TimeStamp to DateTime format.
In this example, I'm using Firebase.
import 'package:intl/intl.dart'; /// Import this line
TimeStamp timestamp = database.data()["date"] /// Firebase firestore date field value.
//Example Outputs:- Timestamp(seconds=1657706107, nanoseconds=261000000)
DateTime dateTime = timestamp.toDate(); /// It will be return Date and Time Both.
//Example Outputs:- 2022-07-13 15:25:07.261
String dateOnly = DateFormat('dd/MM/yyyy').format(dateTime); /// It will be only return date DD/MM/YYYY format
//Example Outputs:- 13/07/2022
In a single-line code
import 'package:intl/intl.dart'; /// Import this line
String dateOnly = DateFormat('dd/MM/yyyy').format(database.data()["date"].toDate()); /// It will be only return date DD/MM/YYYY format
//Example Outputs:- 13/07/2022
Thanks for visiting and pushing my reputation 😍
Happy Coding Journey...🤗

Answer 17

2022
Actually the Flutter team updated the Timestamp object.
Now if you want to convert from Timestamp to DateTime you can just use this code:
/*you Timestamp instance*/.toDate()
eg. Timestamp.now().toDate()
Viceversa if you want to convert from DateTime to Timestamp you can do:
Timestamp.fromDate(/*your DateTime instance*/)
eg. Timestamp.fromDate(DateTime.now())
Hope you'll find this helpfull.

Answer 18

All of that above can work but for a quick and easy fix you can use the time_formatter package.
Using this package you can convert the epoch to human-readable time.
String convertTimeStamp(timeStamp){
//Pass the epoch server time and the it will format it for you
String formatted = formatTime(timeStamp).toString();
return formatted;
}
//Then you can display it
Text(convertTimeStamp['createdTimeStamp'])//< 1 second : "Just now" up to < 730 days : "1 year"
Here you can check the format of the output that is going to be displayed: Formats

Answer 19

Timestamp has [toDate] method then you can use it directly as an DateTime.
timestamp.toDate();
// return DateTime object
Also there is an stupid way if you want really convert it:
DateTime.parse(timestamp.toDate().toString())

Answer 20

Long num format date into Calender format from:
var responseDate = 1637996744;
var date = DateTime.fromMillisecondsSinceEpoch(responseDate);
//to format date into different types to display;
// sample format: MM/dd/yyyy : 11/27/2021
var dateFormatted = DateFormat('MM/dd/yyyy').format(date);
// sample format: dd/MM/yyy : 27/11/2021
var dateFormatted = DateFormat('dd/MM/yyyy').format(date);
// sample format: dd/MMM/yyyy : 27/Nov/2021
var dateFormatted = DateFormat('dd/MMM/yyyy').format(date);
// sample format: dd/MMMM/yyyy : 27/November/2021
var dateFormatted = DateFormat('dd/MMMM/yyyy').format(date);
print("Date After Format = $dateFormatted");

Answer 21

Assuming you have a class
class Dtime {
int dt;
Dtime(this.dt);
String formatYMED() {
var date = DateTime.fromMillisecondsSinceEpoch(this.dt);
var formattedDate = DateFormat.yMMMMEEEEd().format(date);
return formattedDate;
}
String formatHMA() {
var time = DateTime.fromMillisecondsSinceEpoch(this.dt * 1000);
final timeFormat = DateFormat('h:mm a', 'en_US').format(time);
return timeFormat;
}
I am a beginner though, I hope that works.

Answer 22

There are different ways this can be achieved based on different scenario, see which of the following code fits your scenario.
Conversion of Firebase timestamp to DateTime:
document['timeStamp'].toDate()
(document["timeStamp"] as Timestamp).toDate()
DateTime.fromMillisecondsSinceEpoch(document['timeStamp'].millisecondsSinceEpoch);
Timestamp.fromMillisecondsSinceEpoch(document['timeStamp'].millisecondsSinceEpoch).toDate();
If timeStamp is in microseconds use:
DateTime.fromMicrosecondsSinceEpoch(timestamp * 1000000);
If timeStamp is in milliseconds use:
DateTime.fromMillisecondsSinceEpoch(timestamp * 1000);
Add the following function in your dart file.
String formatTimestamp(Timestamp timestamp) {
var format = new DateFormat('yyyy-MM-dd'); // <- use skeleton here
return format.format(timestamp.toDate());
}
call it as formatTimestamp(document['timestamp'])