Cascading drop down list with grid editing in EJ2 TypeScript Grid control

13 Apr 202312 minutes to read
You can achieve the Cascading DropDownList with grid Editing by using the Cell Edit Template feature.
In the below demo, Cascading DropDownList is rendered for the ShipCountry and ShipState column.
index.ts
index.html
import { Grid, Edit, Toolbar } from '@syncfusion/ej2-grids';
import { DropDownList } from '@syncfusion/ej2-dropdowns';
import { Query } from '@syncfusion/ej2-data';
import { data } from './datasource.ts';

Grid.Inject(Edit, Toolbar);

let countryElem: HTMLElement;
let countryObj: DropDownList;

let stateElem: HTMLElement;
let stateObj: DropDownList;

let country: { [key: string]: Object }[] = [
    { countryName: 'United States', countryId: '1' },
    { countryName: 'Australia', countryId: '2' }
];
let state: { [key: string]: Object }[] = [
    { stateName: 'New York', countryId: '1', stateId: '101' },
    { stateName: 'Virginia ', countryId: '1', stateId: '102' },
    { stateName: 'Washington', countryId: '1', stateId: '103' },
    { stateName: 'Queensland', countryId: '2', stateId: '104' },
    { stateName: 'Tasmania ', countryId: '2', stateId: '105' },
    { stateName: 'Victoria', countryId: '2', stateId: '106' }
];

let grid: Grid = new Grid({
    dataSource: data,
    toolbar: ['Add', 'Edit', 'Delete', 'Update', 'Cancel'],
    editSettings: { allowEditing: true, allowAdding: true, allowDeleting: true, mode: 'Normal' },
    columns: [
        { field: 'OrderID', headerText: 'Order ID', textAlign: 'Right', width: 100, isPrimaryKey: true, validationRules: { required: true } },
        { field: 'CustomerID', headerText: 'Customer ID', width: 120, validationRules: { required: true, minLength: 3 } },
        {
            field: 'ShipCountry', headerText: 'Ship Country', width: 120, edit: {
                create: () => {
                    countryElem = document.createElement('input');
                    return countryElem;
                },
                read: () => {
                    return countryObj.text;
                },
                destroy: () => {
                    countryObj.destroy();
                },
                write: () => {
                    countryObj = new DropDownList({
                        dataSource: country,
                        fields: { value: 'countryId', text: 'countryName' },
                        change: () => {
                            stateObj.enabled = true;
                            let tempQuery: Query = new Query().where('countryId', 'equal', countryObj.value);
                            stateObj.query = tempQuery;
                            stateObj.text = null;
                            stateObj.dataBind();
                        },
                        placeholder: 'Select a country',
                        floatLabelType: 'Never'
                    });
                    countryObj.appendTo(countryElem);
                }
            }
        },
        {
            field: 'ShipState', headerText: 'Ship State', width: 150, edit: {
                create: () => {
                    stateElem = document.createElement('input');
                    return stateElem;
                },
                read: () => {
                    return stateObj.text;
                },
                destroy: () => {
                    stateObj.destroy();
                },
                write: () => {
                    stateObj = new DropDownList({
                        dataSource: state,
                        fields: { value: 'stateId', text: 'stateName' },
                        enabled: false,
                        placeholder: 'Select a state',
                        floatLabelType: 'Never'
                    });
                    stateObj.appendTo(stateElem);
                }
            }
        }
    ],
    height: 265
});
grid.appendTo('#Grid');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 Grid</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript Grid Control" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-grids/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-popups/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-richtexteditor/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-navigations/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-dropdowns/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-lists/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-calendars/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-notifications/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/26.1.35/ej2-splitbuttons/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>
    <style>
        .e-row[aria-selected="true"] .e-customizedExpandcell {
            background-color: #e0e0e0;
        }
        .e-grid.e-gridhover tr[role='row']:hover {
            background-color: #eee;
        }
        .e-expand::before {
        content: '\e5b8';
    }
    .empImage {
        margin: 6px 16px;
        float: left;
        width: 50px;
        height: 50px;
    }
    </style>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='Grid'></div>
    </div>
</body>
</html>