DevExtreme React - Handle the Value Change Event

If instead of picking a value, an end user types it into the DateBox, this value applies when the change event is raised. If you need the value to be applied on another event, set the valueChangeEvent option.

jQuery
JavaScript
$(function() {
    $("#dateBoxContainer").dxDateBox({
        value: new Date(),
        type: "date",
        valueChangeEvent: "keyup"
    });
});
Angular
HTML
TypeScript
<dx-date-box
    [(value)]="date"
    type="date"
    valueChangeEvent="keyup">
</dx-date-box>
import { DxDateBoxModule } from "devextreme-angular";
// ...
export class AppComponent {
    date: Date = new Date()
}
@NgModule({
    imports: [
        // ...
        DxDateBoxModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxDateBox
        :value="date"
        type="date"
        value-change-event="keyup"
    />
</template>

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

import DxDateBox from 'devextreme-vue/date-box';

export default {
    components: {
        DxDateBox
    },
    data() {
        return {
            date: new Date()
        };
    }
}
</script>
React
App.js
import React from 'react';
import 'devextreme/dist/css/dx.common.css';
import 'devextreme/dist/css/dx.light.css';

import DateBox from 'devextreme-react/date-box';

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

        this.date = new Date();
    }

    render() {
        return (
            <DateBox
                defaultValue={this.date}
                type="date"
                valueChangeEvent="keyup"
            />
        );
    }
}
export default App;

To process a new DateBox value, you need to handle the value change event. If the handling function is not going to be changed during the lifetime of the widget, assign it to the onValueChanged option when you configure the widget.

jQuery
JavaScript
$(function() {
    $("#dateBoxContainer").dxDateBox({
        // ...
        onValueChanged: function (e) {
            const previousValue = e.previousValue;
            const newValue = e.value;
            // Event handling commands go here
        }
    });
});
Angular
HTML
TypeScript
<dx-date-box ...
    [(value)]="date"
    (onValueChanged)="handleValueChange($event)">
</dx-date-box>
import { DxDateBoxModule } from "devextreme-angular";
// ...
export class AppComponent {
    date: Date = new Date(),
    handleValueChange (e) {
        const previousValue = e.previousValue;
        const newValue = e.value;
        // Event handling commands go here
    }
}
@NgModule({
    imports: [
        // ...
        DxDateBoxModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxDateBox
        :value.sync="date"
        @value-changed="handleValueChange"
    />
</template>

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

import DxDateBox from 'devextreme-vue/date-box';

export default {
    components: {
        DxDateBox
    },
    data() {
        return {
            date: new Date()
        };
    },
    methods: {
        handleValueChange(e) {
            const previousValue = e.previousValue;
            const newValue = e.value;
            // Event handling commands go here
        }
    }
}
</script>
React
App.js
import React from 'react';
import 'devextreme/dist/css/dx.common.css';
import 'devextreme/dist/css/dx.light.css';

import DateBox from 'devextreme-react/date-box';

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

        this.state = {
            date: new Date()
        };
        this.handleValueChange = this.handleValueChange.bind(this);
    }

    handleValueChange(e) {
        const previousValue = e.previousValue;
        const newValue = e.value;
        // Event handling commands go here

        this.setState({
            date: newValue
        });
    }

    render() {
        return (
            <DateBox
                value={this.state.date}
                onValueChanged={this.handleValueChange}
            />
        );
    }
}
export default App;

If you are going to change event handlers at runtime, or if you need to attach several handlers to the value change event, subscribe to this event using the on(eventName, eventHandler) method. This approach is more typical of jQuery.

JavaScript
var valueChangedHandler1 = function (e) {
    var previousValue = e.previousValue;
    var newValue = e.value;
    // First handler of the "valueChanged" event
};

var valueChangedHandler2 = function (e) {
    var previousValue = e.previousValue;
    var newValue = e.value;
    // Second handler of the "valueChanged" event
};

$("#dateBoxContainer").dxDateBox("instance")
    .on("valueChanged", valueChangedHandler1)
    .on("valueChanged", valueChangedHandler2);
See Also