DevExtreme Angular - Time Zone Support
Appointments are displayed in the client time zone. The time-zone offset specified in the startDate or endDate is also taken into account (if there is any). You can force a time zone for an individual appointment via its startDateTimeZone and endDateTimeZone fields or for all appointments in the widget via its timeZone option. timeZone takes precedence over start/endDateTimeZone.
You can use the following formula to calculate an appointment's resulting time-zone offset:
- `resultingOffset` = `timeZoneOffset` - `clientOffset` (or `embeddedOffset` if there is any)
where
timeZoneOffset
is the offset of the timeZone or start/endDateTimeZone.clientOffset
is the offset of the client side.embeddedOffset
is the offset specified in the start/endDate.
The calculated offset is then added to the date-time value.
For example, if the timeZone is "Europe/Berlin" (UTC offset +1), and the client is in Tokyo (UTC offset +9), the calculated offset is 1 - 9 = -8. The time of all appointments is shifted back 8 hours: the appointment that started at 2019-01-01T12:00:00
starts at 2019-01-01T04:00:00
. The same applies when the time-zone offset is specified in the date-time value (2019-01-01T12:00:00+09:00
), except that this offset is used instead of the client offset.
Add the following code to allow users to change an appointment's time zone:
- <dx-scheduler ...
- (onAppointmentFormOpening)="showTimeZoneFields($event)">
- </dx-scheduler>
- import { Component } from '@angular/core';
- @Component({
- selector: 'app-root',
- templateUrl: './app.component.html',
- styleUrls: ['./app.component.css']
- })
- export class AppComponent {
- showTimeZoneFields(e) {
- e.form.itemOption("startDateTimeZone", { visible: true });
- e.form.itemOption("endDateTimeZone", { visible: true });
- }
- }
- import { BrowserModule } from '@angular/platform-browser';
- import { NgModule } from '@angular/core';
- import { AppComponent } from './app.component';
- import { DxSchedulerModule } from 'devextreme-angular';
- @NgModule({
- declarations: [
- AppComponent
- ],
- imports: [
- BrowserModule,
- DxSchedulerModule
- ],
- providers: [],
- bootstrap: [AppComponent]
- })
- export class AppModule { }
To allow a user to change the widget's time zone, implement a select box as shown in the Time Zone Support demo.
If you have technical questions, please create a support ticket in the DevExpress Support Center.