unable to convert string date in Format yyyyMMddHH

问题:

i have a string containing date in format yyyyMMddHHmmss (e.g.) (20180626170555) and i am using following code to convert it into date time

dateTimeFromString(json['dateTime'], "yyyyMMddHHmmss")

exception is:

FormatException: Trying to read MM from 20180623130424 at position 14

what can be the reason?

回答1:

intl DateFormat can't cope with your input string as it doesn't have any separators. The whole string gets consumed as the year. However DateTime.parse does cope with this (nearly). It happens to expect precisely the format you have (again, nearly).

One of the acceptable styles to parse is 20120227T132700, which just differs by the T date/time separator.

Try this:

String date = '20180626170555';
String dateWithT = date.substring(0, 8) + 'T' + date.substring(8);
DateTime dateTime = DateTime.parse(dateWithT);

回答2:

DateTime.parse("string date here") accept some formatted string only. Check below examples of accepted strings.

• "2012-02-27 13:27:00"
• "2012-02-27 13:27:00.123456789z"
• "2012-02-27 13:27:00,123456789z"
• "20120227 13:27:00"
• "20120227T132700"
• "20120227"
• "[phone]"
• "2012-02-27T14Z"
• "2012-02-27T14+00:00"
• "-123450101 00:00:00 Z": in the year -12345.
• "2002-02-27T14:00:00-0500": Same as "2002-02-27T19:00:00Z"

=> String to DateTime

DateTime tempDate = new DateFormat("yyyy-MM-dd hh:mm:ss").parse(savedDateString);

=> DateTime to String

String date = DateFormat("yyyy-MM-dd hh:mm:ss").format(DateTime.now());

Reference links:

• Use intl for DateFormat from flutter package (https://pub.dev/packages/intl)
• DateTime.parse() => https://api.dart.dev/stable/2.7.2/dart-core/DateTime/parse.html

回答3:

You can use DateFormat to parse a DateTime from string to an object

// With en_US locale by default
var newDateTimeObj = new DateFormat().add_yMd().add_Hms().parse("7/10/1996 10:07:23")
// with a defined format
var newDateTimeObj2 = new DateFormat("dd/MM/yyyy HH:mm:ss").parse("10/02/2000 15:13:09")

Check the doc here.

回答4:

From the docs, you need Single M to month in year :

dateTimeFromString(json['dateTime'], "yMdHms")

回答5:

Basic information about how to convert String to Date and Date to string in flutter. Look at below link

https://quickstartflutterdart.blogspot.com/2018/10/how-to-convert-string-to-date-and-date.html

Might be it will be helped for others.

回答6:

Thanks to @Richard_Heap this did my trick

new Text(timeago.format(DateTime.parse(mytimestring))