Create a User-Defined Item

A user can select existing values and add new values to the TagBox. To enable this feature, assign true to the acceptCustomValue property.

Note that you need to implement the onCustomItemCreating function to create a new data source entry. You can specify DOM events after which the component calls this function. Use the customItemCreateEvent property for this purpose. In addition to the event passed to this property, the item can also be created when users press the Enter key.

jQuery
HTML
JavaScript
<div id="tagBoxContainer"></div>
const tagBoxData = new DevExpress.data.DataSource({
    store: [
        { id: 1, firstName: "Andrew" },
        { id: 2, firstName: "Nancy" },
        { id: 3, firstName: "Steven" }
    ]
});

$("#tagBoxContainer").dxTagBox({
    dataSource: tagBoxData,
    valueExpr: 'id',
    displayExpr: 'firstName',
    acceptCustomValue: true,
    customItemCreateEvent: 'focusout',
    onCustomItemCreating: function(e){
        // Generates a new 'id'
        let nextId;
        tagBoxData.store().totalCount().done(count => {nextId = count + 1});
        // Creates a new entry
        e.customItem = { id: nextId, firstName: e.text };
        // Adds the entry to the data source
        tagBoxData.store().insert(e.customItem);
        // Reloads the data source
        tagBoxData.reload();
    }
});
Angular
HTML
TypeScript
<dx-tag-box
    [dataSource]="tagBoxData"
    valueExpr="id"
    displayExpr="firstName"
    [acceptCustomValue]="true"
    customItemCreateEvent="focusout"
    (onCustomItemCreating)="onCustomItemCreating($event)">
</dx-tag-box>
import DataSource from "devextreme/data/data_source";
import { DxTagBoxModule } from "devextreme-angular";
// ...
export class AppComponent {
    tagBoxData: DataSource = new DataSource({
        store: [
            { id: 1, firstName: "Andrew" },
            { id: 2, firstName: "Nancy" },
            { id: 3, firstName: "Steven" }
        ]
    });
    onCustomItemCreating (e) {
        // Generates a new 'id'
        let nextId;
        tagBoxData.store().totalCount().done(count => {nextId = count + 1});
        // Creates a new entry
        e.customItem = { id: nextId, firstName: e.text };
        // Adds the entry to the data source
        this.tagBoxData.store().insert(e.customItem);
        // Reloads the data source
        this.tagBoxData.reload();
    }
}
@NgModule({
     imports: [
         // ...
         DxTagBoxModule
     ],
     // ...
 })
Vue
<template>
    <DxTagBox
        :data-source="tagBoxData"
        :accept-custom-value="true"
        value-expr="id"
        display-expr="firstName"
        custom-item-create-event="focusout"
        @custom-item-creating="onCustomItemCreating"
    />
</template>

<script>
import 'devextreme/dist/css/dx.light.css';

import { DxTagBox } from 'devextreme-vue/tag-box';
import DataSource from "devextreme/data/data_source";

export default {
    components: {
        DxTagBox
    },
    data() {
        return {
            tagBoxData: new DataSource({
                store: [
                    { id: 1, firstName: "Andrew" },
                    { id: 2, firstName: "Nancy" },
                    { id: 3, firstName: "Steven" }
                ]
            });
        };
    },
    methods: {
        onCustomItemCreating(e) {
            // Generates a new 'id'
            let nextId;
            tagBoxData.store().totalCount().done(count => {nextId = count + 1});
            // Creates a new entry
            e.customItem = {
                id: nextId,
                firstName: e.text
            };
            // Adds the entry to the data source
            this.tagBoxData.store().insert(e.customItem);
            // Reloads the data source
            this.tagBoxData.reload();
        }
    }
}
</script>
React
import React from 'react';
import 'devextreme/dist/css/dx.light.css';

import { TagBox } from 'devextreme-react/tag-box';
import DataSource from "devextreme/data/data_source";

const tagBoxData = new DataSource({
    store: [
        { id: 1, firstName: "Andrew" },
        { id: 2, firstName: "Nancy" },
        { id: 3, firstName: "Steven" }
    ]
});

class App extends React.Component {
    constructor(props) {
        super(props);

        this.onCustomItemCreating = this.onCustomItemCreating.bind(this);
    }

    onCustomItemCreating(e) {
        // Generates a new 'id'
        let nextId;
        tagBoxData.store().totalCount().done(count => {nextId = count + 1});
        // Creates a new entry
        e.customItem = {
            id: nextId,
            firstName: e.text
        };
        // Adds the entry to the data source
        tagBoxData.store().insert(e.customItem);
        // Reloads the data source
        tagBoxData.reload();
    }

    render() {
        return (
            <TagBox
                dataSource={tagBoxData}
                acceptCustomValue={true}
                valueExpr="id"
                displayExpr="firstName"
                customItemCreateEvent="focusout"
                onCustomItemCreating={this.onCustomItemCreating}
            />
        );
    }
}

export default App;
See Also