Timezone in React Gantt component

2 Feb 202318 minutes to read

The Gantt makes use of the current system time zone by default. If it needs to follow some other user-specific time zone, then the timezone property needs to be used.

Understanding date manipulation in JavaScript

The new Date() in JavaScript returns the exact current date object with complete time and timezone information. For example, it may return value such as Wed Dec 12 2018 05:23:27 GMT+0530 (India Standard Time) which indicates that the current date is December 12, 2018 and the current time is 5.23 AM on browsers following the IST timezone.

Display same time everywhere with no time difference

Setting timezone to UTC for Gantt will display the same time as in the database for all the users in different time zone.

index.jsx
index.tsx
index.html
import * as React from 'react';
import * as ReactDOM from 'react-dom';
import { GanttComponent, Inject,Edit, Selection } from '@syncfusion/ej2-react-gantt';
import { timezoneData } from './datasource';

function App(){
  const taskFields = {
    id: 'taskID',
    name: 'taskName',
    startDate: 'startDate',
    duration: 'duration',
    progress: 'progress',
    dependency: 'predecessor',
    parentID: 'ParentId'
  };
  const timelineSettings = {
    timelineUnitSize: 65,
    topTier: {
        unit: 'Day',
        format: 'MMM dd, yyyy'
    },
    bottomTier: {
        unit: 'Hour',
        format: 'hh:mm a'
    }
  };
  let dayWorkingTime = [{ from: 0, to: 24 }];
  return (
    <GanttComponent 
      dataSource={timezoneData} 
      taskFields={taskFields}
      timelineSettings={timelineSettings} 
      allowSelection={true}
      timezone='UTC' 
      height='450px' 
      dateFormat='hh:mm a'
      dayWorkingTime={dayWorkingTime} 
      durationUnit='Hour' 
      includeWeekend={true}
    >
        <Inject services={[Edit, Selection]} />
    </GanttComponent>
  );
};
ReactDOM.render(<App />, document.getElementById('root'));
import * as React from 'react';
import * as ReactDOM from 'react-dom';
import { GanttComponent, Inject,Edit, Selection } from '@syncfusion/ej2-react-gantt';
import { timezoneData } from './datasource';

function App(){
  const taskFields: any = {
    id: 'taskID',
    name: 'taskName',
    startDate: 'startDate',
    duration: 'duration',
    progress: 'progress',
    dependency: 'predecessor',
    parentID: 'parentID'
  };
  const timelineSettings: any = {
    timelineUnitSize: 65,
    topTier: {
        unit: 'Day',
        format: 'MMM dd, yyyy'
    },
    bottomTier: {
        unit: 'Hour',
        format: 'hh:mm a'
    }
  };
  let  dayWorkingTime: any = [{ from: 0, to: 24 }];
  return (
    <GanttComponent 
      dataSource={timezoneData} 
      taskFields={taskFields}
      timelineSettings={timelineSettings} 
      allowSelection={true}
      timezone='UTC' 
      height='450px' 
      dateFormat='hh:mm a'
      dayWorkingTime={dayWorkingTime} 
      durationUnit='Hour' 
      includeWeekend={true}
    >
      <Inject services={[Edit, Selection]} />
    </GanttComponent>
  ); 
};
ReactDOM.render(<App />, document.getElementById('root'));
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Syncfusion React Gantt</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Essential JS 2 for React Components" />
    <meta name="author" content="Syncfusion" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/material.css" rel="stylesheet" type="text/css"/>
    <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
     <style>
        #loader {
            color: #008cff;
            height: 40px;
            left: 45%;
            position: absolute;
            top: 45%;
            width: 30%;
        }
    </style>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
        <div id='root'>
            <div id='loader'>Loading....</div>
        </div>
</body>

</html>

CRUD operations with timezone

CRUD operations can be performed with timezone, and the gantt is rendered based on the timezone specified in the load time. All the editing actions will be done based on the user timezone, but on database save action, we have reversed this conversion to local time and provided data to client side events for better understanding purpose. Refer to the following code example.

index.jsx
index.tsx
index.html
import * as React from 'react';
import * as ReactDOM from 'react-dom';
import { GanttComponent, Inject, Selection, Edit } from '@syncfusion/ej2-react-gantt';
import { timezoneData } from './datasource';

function App(){
  const taskFields = {
    id: 'taskID',
    name: 'taskName',
    startDate: 'startDate',
    duration: 'duration',
    progress: 'progress',
    dependency: 'predecessor',
    parentID: 'parentId'
  };
  const editSettings = {
    allowAdding: true,
    allowEditing: true,
    allowDeleting: true,
    allowTaskbarEditing: true,
    showDeleteConfirmDialog: true
  };
  const timelineSettings= {
    timelineUnitSize: 65,
    topTier: {
      unit: 'Day',
      format: 'MMM dd, yyyy'
    },
    bottomTier: {
      unit: 'Hour',
      format: 'hh:mm a'
    }
  };
  function actionComplete(args) {
    if(args.action == "TaskbarEditing") {
      console.log(args.data.ganttProperties.endDate);
    }
  }
  let dayWorkingTime = [{ from: 0, to: 24 }];
  return (
    <GanttComponent 
      dataSource={timezoneData} 
      taskFields={taskFields} 
      editSettings={editSettings} 
      allowSelection={true} 
      durationUnit='Hour' 
      actionComplete={actionComplete}  
      height = '450px' 
      includeWeekend={true} 
      dayWorkingTime={dayWorkingTime} 
      timelineSettings={timelineSettings} 
    >
      <Inject services={[Edit, Selection]} />
    </GanttComponent>
  );
};
ReactDOM.render(<App />, document.getElementById('root'));
import * as React from 'react';
import * as ReactDOM from 'react-dom';
import { GanttComponent, Inject, Selection, Edit } from '@syncfusion/ej2-react-gantt';
import { timezoneData } from './datasource';

function App(){
  const taskFields: any = {
    id: 'taskID',
    name: 'taskName',
    startDate: 'startDate',
    duration: 'duration',
    progress: 'progress',
    dependency: 'predecessor',
    parentID: 'parentId'
  };
  const editSettings: any = {
    allowAdding: true,
    allowEditing: true,
    allowDeleting: true,
    allowTaskbarEditing: true,
    showDeleteConfirmDialog: true
  };
  const timelineSettings: any = {
    timelineUnitSize: 65,
    topTier: {
      unit: 'Day',
      format: 'MMM dd, yyyy'
    },
    bottomTier: {
      unit: 'Hour',
      format: 'hh:mm a'
    }
  };
  function actionComplete(args: any) {
    if(args.action == "TaskbarEditing") {
      console.log(args.data.ganttProperties.endDate);
    }
  }
  let dayWorkingTime: any = [{ from: 0, to: 24 }];
  return (
    <GanttComponent 
      dataSource={timezoneData} 
      taskFields={taskFields} 
      editSettings={editSettings} 
      allowSelection={true} 
      durationUnit='Hour' 
      actionComplete={actionComplete}  
      height = '450px' 
      includeWeekend={true} 
      dayWorkingTime={dayWorkingTime} 
      timelineSettings={timelineSettings} 
    >
      <Inject services={[Edit, Selection]} />
    </GanttComponent>
  );
};
ReactDOM.render(<App />, document.getElementById('root'));
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Syncfusion React Gantt</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Essential JS 2 for React Components" />
    <meta name="author" content="Syncfusion" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/material.css" rel="stylesheet" type="text/css"/>
    <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
     <style>
        #loader {
            color: #008cff;
            height: 40px;
            left: 45%;
            position: absolute;
            top: 45%;
            width: 30%;
        }
    </style>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
        <div id='root'>
            <div id='loader'>Loading....</div>
        </div>
</body>

</html>

Timezone methods

offset

This method is used to calculate the difference between passed UTC date and timezone.

Parameters	Type	Description
Date	Date	UTC time as date object.
Timezone	String	Timezone.

Returns number

    // Assume your local timezone as IST/UTC+05:30
    let timezone: Timezone = new Timezone();
    let date: Date = new Date(2018,11,5,15,25,11);
    let timeZoneOffset: number = timezone.offset(date,"Europe/Paris");
    console.log(timeZoneOffset); //-60

convert

This method is used to convert the passed date from one timezone to another timezone.

Parameters	Type	Description
Date	Date	UTC time as date object.
fromOffset	number/string	Timezone from which date need to be converted.
toOffset	number/string	Timezone to which date need to be converted.

Returns Date

    // Assume your local timezone as IST/UTC+05:30
    let timezone: Timezone = new Timezone();
    let date: Date = new Date(2018,11,5,15,25,11);
    let convertedDate: Date = timezone.convert(date, "Europe/Paris", "Asia/Tokya");
    let convertedDate1: Date = timezone.convert(date, 60, -360);
    console.log(convertedDate); //2018-12-05T08:55:11.000Z
    console.log(convertedDate1); //2018-12-05T16:55:11.000Z

remove

This method is used to remove the time difference between passed UTC date and timezone.

Parameters	Type	Description
Date	Date	UTC as date object.
Timezone	String	Timezone.

Returns Date

    // Assume your local timezone as IST/UTC+05:30
    let timezone: Timezone = new Timezone();
    let date: Date = new Date(2018,11,5,15,25,11);
    let convertedDate: Date = timezone.remove(date, "Europe/Paris");
    console.log(convertedDate); //2018-12-05T14:25:11.000Z