Data binding in EJ2 TypeScript Multi select control
2 May 202313 minutes to read
The MultiSelect loads the data either from local data sources or remote data services using the dataSource property. It supports the data type of array
or DataManager
.
The MultiSelect also supports different kinds of data services such as OData, OData V4, and Web API, and data formats such as XML, JSON, and JSONP with the help of DataManager
adaptors.
Fields | Type | Description |
---|---|---|
text | string |
Specifies the display text of each list item. |
value | number or string |
Specifies the hidden data value mapped to each list item that should contain a unique value. |
groupBy | string |
Specifies the category under which the list item has to be grouped. |
iconCss | string |
Specifies the icon class of each list item. |
When binding complex data to the MultiSelect, fields should be mapped correctly. Otherwise, the selected item remains undefined.
Binding local data
Local data can be represented in two ways as described below.
1. Array of string
The MultiSelect has support to load array of primitive data such as strings and numbers. Here, both value and text field act the same.
import { MultiSelect } from '@syncfusion/ej2-dropdowns';
// define the array of data
let sportsData: string[] = ['Badminton', 'Cricket', 'Football', 'Golf', 'Tennis'];
// initialize MultiSelect component
let msObject: MultiSelect = new MultiSelect({
//set the data to dataSource property
dataSource: sportsData,
// set placeholder to multiSelect input element
placeholder: "Select games"
});
// render initialized multiSelect
msObject.appendTo('#select');
<!DOCTYPE html>
<html lang="en">
<head>
<title>Essential JS 2 MultiSelect</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Typescript UI Controls" />
<meta name="author" content="Syncfusion" />
<link href="styles.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-base/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-inputs/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-dropdowns/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-buttons/styles/material.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
<script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
<div id='loader'>LOADING....</div>
<div id='container' style="margin:0 auto; width:250px;">
<input type="text" tabindex="1" id='select' />
</div>
</body>
</html>
2. Array of object
The MultiSelect can generate its list items through an array of complex data. For this, the appropriate columns should be mapped to the fields property.
In the following example, id
column and sports
column from complex data have been mapped to the value
field and text
field, respectively.
import { MultiSelect } from '@syncfusion/ej2-dropdowns';
//define the array of complex data
let sportsData: { [key: string]: Object }[] = [
{ id: 'game1', sports: 'Badminton' },
{ id: 'game2', sports: 'Football' },
{ id: 'game3', sports: 'Tennis' }
];
//initiate the MultiSelect
let msObject: MultiSelect = new MultiSelect({
// bind the sports Data to datasource property
dataSource: sportsData,
// maps the appropriate column to fields property
fields: { text: 'sports', value: 'id' },
//set the placeholder to MultiSelect input
placeholder:"Select games"
});
//render the component
msObject.appendTo('#select');
<!DOCTYPE html>
<html lang="en">
<head>
<title>Essential JS 2 MultiSelect</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Typescript UI Controls" />
<meta name="author" content="Syncfusion" />
<link href="styles.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-base/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-inputs/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-dropdowns/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-buttons/styles/material.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
<script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
<div id='loader'>LOADING....</div>
<div id='container' style="margin:0 auto; width:250px;">
<br>
<!--element which is going to render the MultiSelect-->
<input type="text" tabindex="1" id='select' />
</div>
</body>
</html>
3. Array of complex object
The MultiSelect can generate its list items through an array of complex data. For this, the appropriate columns should be mapped to the fields property.
In the following example, Code.Id
column and Country.Name
column from complex data have been mapped to the value
field and text
field, respectively.
import { MultiSelect } from '@syncfusion/ej2-dropdowns';
//define the array of complex data
let countriesData: { [key: string]: Object }[] = [
{ Country: { Name: 'Australia' }, Code: { Id: 'AU' }},
{ Country: { Name: 'Bermuda' },Code: { Id: 'BM' }},
{ Country:{ Name: 'Canada'}, Code:{ Id: 'CA'} },
{ Country:{Name: 'Cameroon'}, Code:{ Id: 'CM'} },
{ Country:{Name: 'Denmark'}, Code:{ Id: 'DK' }},
{ Country:{Name: 'France'}, Code: { Id:'FR'} }
];
//initiate the MultiSelect
let msObject: MultiSelect = new MultiSelect({
// bind the sports Data to datasource property
dataSource: countriesData,
// maps the appropriate column to fields property
fields: { text: 'Country.Name', value: 'Code.Id' },
//set the placeholder to MultiSelect input
placeholder:"Select a country"
});
//render the component
msObject.appendTo('#select');
<!DOCTYPE html>
<html lang="en">
<head>
<title>Essential JS 2 MultiSelect</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Typescript UI Controls" />
<meta name="author" content="Syncfusion" />
<link href="styles.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-base/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-inputs/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-dropdowns/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-buttons/styles/material.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
<script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
<div id='loader'>LOADING....</div>
<div id='container' style="margin:0 auto; width:250px;">
<br>
<!--element which is going to render the MultiSelect-->
<input type="text" tabindex="1" id='select' />
</div>
</body>
</html>
Binding remote data
The MultiSelect supports retrieval of data from remote data services with the help of DataManager
component. The Query property is used to fetch data from the database and bind it to the MultiSelect.
The following sample displays the first 6 contacts from “Customers” table of the Northwind
Data Service.
import { MultiSelect } from '@syncfusion/ej2-dropdowns';
//import DataManager related classes
import { Query, DataManager, ODataV4Adaptor } from '@syncfusion/ej2-data';
//initiates the component
let customers: MultiSelect = new MultiSelect({
//bind the DataManager instance to dataSource property
dataSource: new DataManager({
url: 'https://services.odata.org/V4/Northwind/Northwind.svc/',
adaptor: new ODataV4Adaptor,
crossDomain: true
}),
//bind the Query instance to query property
query: new Query().from('Customers').select(['ContactName', 'CustomerID']).take(6),
//map the appropriate columns to fields property
fields: { text: 'ContactName', value: 'CustomerID' },
//set the placeholder to MultiSelect input
placeholder:"Select customers",
//sort the resulted items
sortOrder: 'Ascending'
});
//render the component
customers.appendTo('#select');
<!DOCTYPE html>
<html lang="en">
<head>
<title>Essential JS 2 MultiSelect</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Typescript UI Controls" />
<meta name="author" content="Syncfusion" />
<link href="styles.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-base/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-inputs/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-dropdowns/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.2.2/ej2-buttons/styles/material.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
<script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
<div id='loader'>LOADING....</div>
<div id='container' style="margin:0 auto; width:250px;">
<br>
<!--element which is going to render the MultiSelect-->
<input type="text" tabindex="1" id='select' />
</div>
</body>
</html>