I'm trying to convert a DateTime runtimetype value to Expression<DateTime, DateTimeType>. I've been trying to achieve this for almost three days now. I have tried different approaches but non is working.
The reason I want to achieve this is because moor_flutter library in some cases uses and accepts the library's custom runtimetypes on methods and and the parameter values on those methods.
Below is the sample code;
final DateTime dateToday = new DateTime.now(); // convert DateTime to Expression<DateTime, DateTimeType>
var dateWithNewRuntimetype; // assign the converted value to this variable
I thought I fixed this issue by adding as as Expression<DateTime, DateTimeType> to the value of dateWithNewRuntimetype variable value but no this is not the solution either.
The solution will work on the code below
Stream<List> getLoansWithTomorrowDueDate(int dayInFuture) {
return (select(loans)
..where((l) => l.due_date.isBetween(
dateToday, // it should be Expression<DateTime, DateTimeType> not DateTIme
futureDate, // it should be Expression<DateTime, DateTimeType> not DateTIme)))
.watch();
}
If you want me to provide more info on this I will do so.
Thank you, so much Love.
The isBetween is compared withSqlType.
You must use isBetweenValues.
/// Defines extension functions to express comparisons in sql
extension ComparableExpr<DT, ST extends ComparableType<DT>>
on Expression<DT, ST> {
Expression<bool, BoolType> isBetween(
Expression<DT, ST> lower, Expression<DT, ST> higher,
{bool not = false});
Expression<bool, BoolType> isBetweenValues(DT lower, DT higher,
{bool not = false});
}
Related
Say I have a string
"1974-03-20 00:00:00.000"
It is created using DateTime.now(),
how do I convert the string back to a DateTime object?
DateTime has a parse method
var parsedDate = DateTime.parse('1974-03-20 00:00:00.000');
https://api.dartlang.org/stable/dart-core/DateTime/parse.html
There seem to be a lot of questions about parsing timestamp strings into DateTime. I will try to give a more general answer so that future questions can be directed here.
Your timestamp is in an ISO format. Examples: 1999-04-23, 1999-04-23 13:45:56Z, 19990423T134556.789. In this case, you can use DateTime.parse or DateTime.tryParse. (See the DateTime.parse documentation for the precise set of allowed inputs.)
Your timestamp is in a standard HTTP format. Examples: Fri, 23 Apr 1999 13:45:56 GMT, Friday, 23-Apr-99 13:45:56 GMT, Fri Apr 23 13:45:56 1999. In this case, you can use dart:io's HttpDate.parse function.
Your timestamp is in some local format. Examples: 23/4/1999, 4/23/99, April 23, 1999. You can use package:intl's DateFormat class and provide a pattern specifying how to parse the string:
import 'package:intl/intl.dart';
...
var dmyString = '23/4/1999';
var dateTime1 = DateFormat('d/M/y').parse(dmyString);
var mdyString = '04/23/99';
var dateTime2 = DateFormat('MM/dd/yy').parse(mdyString);
var mdyFullString = 'April 23, 1999';
var dateTime3 = DateFormat('MMMM d, y', 'en_US').parse(mdyFullString));
See the DateFormat documentation for more information about the pattern syntax.
DateFormat limitations:
DateFormat cannot parse dates that lack explicit field separators. For such cases, you can resort to using regular expressions (see below).
Prior to version 0.17.0 of package:intl, yy did not follow the -80/+20 rule that the documentation describes for inferring the century, so if you use a 2-digit year, you might need to adjust the century afterward.
As of writing, DateFormat does not support time zones. If you need to deal with time zones, you will need to handle them separately.
Last resort: If your timestamps are in a fixed, known, numeric format, you always can use regular expressions to parse them manually:
var dmyString = '23/4/1999';
var re = RegExp(
r'^'
r'(?<day>[0-9]{1,2})'
r'/'
r'(?<month>[0-9]{1,2})'
r'/'
r'(?<year>[0-9]{4,})'
r'$',
);
var match = re.firstMatch(dmyString);
if (match == null) {
throw FormatException('Unrecognized date format');
}
var dateTime4 = DateTime(
int.parse(match.namedGroup('year')!),
int.parse(match.namedGroup('month')!),
int.parse(match.namedGroup('day')!),
);
See https://stackoverflow.com/a/63402975/ for another example.
(I mention using regular expressions for completeness. There are many more points for failure with this approach, so I do not recommend it unless there's no other choice. DateFormat usually should be sufficient.)
import 'package:intl/intl.dart';
DateTime brazilianDate = new DateFormat("dd/MM/yyyy").parse("11/11/2011");
you can just use : DateTime.parse("your date string");
for any extra formating, you can use "Intl" package.
void main() {
var dateValid = "30/08/2020";
print(convertDateTimePtBR(dateValid));
}
DateTime convertDateTimePtBR(String validade)
{
DateTime parsedDate = DateTime.parse('0001-11-30 00:00:00.000');
List<String> validadeSplit = validade.split('/');
if(validadeSplit.length > 1)
{
String day = validadeSplit[0].toString();
String month = validadeSplit[1].toString();
String year = validadeSplit[2].toString();
parsedDate = DateTime.parse('$year-$month-$day 00:00:00.000');
}
return parsedDate;
}
a string can be parsed to DateTime object using Dart default function DateTime.parse("string");
final parsedDate = DateTime.parse("1974-03-20 00:00:00.000");
Example on Dart Pad
String dateFormatter(date) {
date = date.split('-');
DateFormat dateFormat = DateFormat("yMMMd");
String format = dateFormat.format(DateTime(int.parse(date[0]), int.parse(date[1]), int.parse(date[2])));
return format;
}
I solved this by creating, on the C# server side, this attribute:
using Newtonsoft.Json.Converters;
public class DartDateTimeConverter : IsoDateTimeConverter
{
public DartDateTimeConverter()
{
DateTimeFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ss.FFFFFFK";
}
}
and I use it like this:
[JsonConverter(converterType: typeof(DartDateTimeConverter))]
public DateTimeOffset CreatedOn { get; set; }
Internally, the precision is stored, but the Dart app consuming it gets an ISO8601 format with the right precision.
HTH
A similar question to a previous one I asked, but the difference being that this not for direct rendering from an underlying field - it's instead part of a some SSJS.
This is for a view column which displays the result of a SSJS function, which returns HTML that gets rendered. This HTML includes a date from a DateTime field, which gets converted to text using #Text. The problem I have with this is, #Text converts dates using the locale settings of the server, not the browser.
Is there an alternative to #Text(dateValue,"D0S0") that's browser locale aware?
The most "XPagey" way to do this is to use a date/time converter. For example (using a stand-in for the computed value):
<xp:viewColumn columnName="">
<xp:this.value><![CDATA[#{javascript:
new java.util.Date()
}]]></xp:this.value>
<xp:this.converter>
<xp:convertDateTime type="both"/>
</xp:this.converter>
</xp:viewColumn>
That "convertDateTime", with its built-in formats, will respect the browser's provided locale. If you set the option in the Xsp Properties to use the browser's time zone and "Round trip", it should also respect the user's time zone.
I've managed to get round this by using DateFormat.getDateInstance. The only problem with this is it doesn't return a short date in the same format as the XPage date converter (no leading zeros and a 2-figure year). I've got round this though with some fiddling around with the string after.
Here's the full function:
function returnLocalShortDate(ndtDate) {
// Receives NotesDateTime object, Java date or string; returns localised date string in XPages short date format
importPackage(java.text);
if (#IsText(ndtDate)) { // string
var jsDate = #TextToTime(ndtDate);
} else if (ndtDate instanceof Date) { // Java date
var jsDate:Date = ndtDate;
} else if (#IsTime(ndtDate)) { // Notes date/time
var jsDate:Date = ndtDate[0].toJavaDate();
} else {
return("");
}
var strDate:String = java.text.DateFormat.getDateInstance(DateFormat.SHORT, context.getLocale()).format(jsDate);
var strYear = jsDate.getFullYear();
var strDateArray = strDate.split("/");
strDate = ('0' + strDateArray[0]).slice(-2) + '/' + ('0' + strDateArray[1]).slice(-2) + '/' + strYear;
return(strDate);
}
Actually, if you know the format you want, rather than what the user might want via their browser settings, you should use the SimpleDateFormatter class. You can supply the format in accordance with whatever pattern you want from the javadocs for that class. If you supply the NotesDocument object and the field name, this returns the date in dd-MMM-yyyy format.
function getFormattedDate ( doc:NotesDocument, fieldName:String ) {
importPackage(java.text);
var dateFormatter:java.text.SimpleDateFormat = new SimpleDateFormat("dd-MMM-yyyy");
var d:Date = new Date(#Today());
if ( doc.hasItem (fieldName) ) {
var valueVector:java.util.Vector = doc.getItemValueDateTimeArray(fieldName);
var iterator = valueVector.iterator();
while (iterator.hasNext()) {
var itemvalue = iterator.next();
if ((typeof(itemvalue)).endsWith("DateTime")) {
d = new Date(itemvalue.toJavaDate());
return dateFormatter.format(d);
}
}
} else {
return fieldName + " is not on the document"
}
}
I owe credit to Declan Lynch's blog entry on date formatting, which takes a little debugging because SSJS returns the date value as an Vector now.
var clientString = "{\"max\":1214.704958677686}";
JObject o = JObject.Parse(clientString);
var jsonString = o.ToString();
contents of jsonString:
{
"max": 1214.7049586776859
}
this is both in visualizing the object and in doing ToString(). Note that the 686 has mysteriously been expanded to 6859 (precision added). This is a problem for us because the numbers are not exactly the same, and a hash function over the json later does not match.
#Ilija Dimov is correct--JSON.NET parses JSON floats as doubles by default. If you still want to use JObject instead of creating a full blown POCO for deserialization, you can use a JsonTextReader and set the FloatParseHandling option:
var reader = new JsonTextReader(new StringReader(clientString));
reader.FloatParseHandling = FloatParseHandling.Decimal;
JObject obj = JObject.Load(reader);
Console.WriteLine(obj["max"].Value<decimal>()); // 1214.704958677686
The reason your value is changed is because of the nature of floating point numbers in .NET. The JObject.Parse(clientString) method at some point executes the following line:
double d;
double.TryParse("1214.704958677686", NumberStyles.Float | NumberStyles.AllowThousands, CultureInfo.InvariantCulture, out d);
where d represents the number that you get in the JObject.
As d is of type double and double is floating point number, you didn't get the value you expect. Read more about Binary floating point and .NET.
There is an option in JSON.NET for parsing floating point numbers as decimals and get the precision you need, but to do that you need to create custom class that matches your json string and deserialize the json. Something like this:
public class MyClass
{
[JsonProperty("max")]
public decimal Max { get; set; }
}
var obj = JsonConvert.DeserializeObject<MyClass>(clientString, new JsonSerializerSettings
{
FloatParseHandling = FloatParseHandling.Decimal
});
By using this code sample, the value of max property won't be changed.
You can experiment this behaviour just by parsing to float, double and decimal:
Assert.AreEqual(1214.705f,float.Parse("1214.704958677686"));
Assert.AreEqual(1214.7049586776859, double.Parse("1214.704958677686"));
Assert.AreEqual(1214.704958677686, decimal.Parse("1214.704958677686"));
So json.net is using double as an intermediate type. You can change this by setting FloatParseHandling option.
I am taking date input from user in text field, which is in format DD/MM/YYYY.
How to convert this string to date object in Flex.
Platform: Adobe Flash Builder 4.6
Since Flex SDK 4.10.0 you can use
DateFormatter.parseDateString(s, "DD/MM/YYYY");
Former versions of parseDateString didn't respect a format string, so it cannot parse dateString value formatted with non default en_US format
Use DateField's stringToDate method. DateFormatter also has a parseDateString function but for some reason it's set to protected.
public function convertStringToDate(s:String):Date
{
return DateField.stringToDate(s, "DD/MM/YYYY");
}
If you are not on the latest Apache SDK (I know we aren't because of third party components) you basically have to write your own conversion.
The built in DateFormatter has the static method, parseDateString, but you have no way of specifying the format of the string. It was a bit rubbish!
If you definitely have no localisation issues and are sure the date is ALWAYS in DD/MM/YYYY format you could use the following:
public function stringToDate(date:String):Date {
// Extract year, month and day from passed in date string
var year:int = IntFromSubString(date, 6, 4);
var month:int = IntFromSubString(date, 3, 2);
var day:int = IntFromSubString(date, 0, 2);
// Always remember Flex months start from 0 (Jan=0, Feb=1 etc.) so take 1 off the parsed month
return new Date(year, month-1, day);
}
private static function IntFromSubString(date:String, start:int, length:int):int {
return parseInt(date.substr(start, length)) as int;
}
Could someone explain why the FLEX 4.5 XMLDecoder does this to my XML-data?
var decoder:XMLDecoder = new XMLDecoder;
var $object:Object = decoder.decode( <xmltag>08.00</xmltag> );
// object = "08.00"
var decoder:XMLDecoder = new XMLDecoder;
var $object:Object = decoder.decode( <xmltag>11.00</xmltag> );
// Object = "11" (HEY! Where did my '.00' part of the string go?)
var decoder:XMLDecoder = new XMLDecoder;
var $object:Object = decoder.decode( <xmltag>11.30</xmltag> );
// Object = "11.3" (HEY! Where did my '0' part of the string go?)
The Flex deserializer also gave me issues with this. It may be interpreting them as Number objects and thus they will return short representations when toString() is called.
Try using .toFixed(2) whenever you need to print a value such as 11.00
var $object:Object = decoder.decode( <xmltag>11.00</xmltag> );
trace($object); //11
trace($object.toFixed(2)); //11.00
So, to the answer the original question of why this is happening:
In the source code for SimpleXMLDecoder (which I'm guessing has similar functionality to XMLDecoder), there's a comment in the function simpleType():
//return the value as a string, a boolean or a number.
//numbers that start with 0 are left as strings
//bForceObject removed since we'll take care of converting to a String or Number object later
numbers that start with 0 are left as strings - I guess they thought of phone numbers but not decimals.
Also, because of some hacky implicit casting, you actually have three different types -
"0.800" : String
11 : int
11.3: Number